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Impact of Oxygen Vacancy on Performance of Amorphous InGaZnO Based Schottky Barrier Diode 被引量:1
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作者 JIA Bin TONG Xiaowen +3 位作者 HAN Zikang QIN Ming WANG Lifeng HUANG Xiaodong 《发光学报》 北大核心 2025年第3期412-420,共9页
Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hin... Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hinder system integration due to their specific manufacturing processes.Conversely,metal oxide diodes,with their simple fabrication techniques,offer advantages for system integration.The oxygen vacancy defect of oxide semiconductor will greatly affect the electrical performance of the device,so the performance of the diode can be effectively controlled by adjusting the oxygen vacancy concentration.This study centers on optimizing the performance of diodes by modulating the oxygen vacancy concentration within InGaZnO films through control of oxygen flows during the sputtering process.Experimental results demonstrate that the diode exhibits a forward current density of 43.82 A·cm^(−2),with a rectification ratio of 6.94×10^(4),efficiently rectifying input sine signals with 1 kHz frequency and 5 V magnitude.These results demonstrate its potential in energy conversion and management.By adjusting the oxygen vacancy,a methodology is provided for optimizing the performance of rectifying diodes. 展开更多
关键词 INGAZNO Schottky barrier diode oxygen vacancy rectifying performance
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基于light-oxygen-voltage(LOV)结构域光敏剂的细胞毒性研究
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作者 许爽 万奔 +1 位作者 沙娜 赵开弘 《生物化学与生物物理进展》 北大核心 2025年第2期487-500,共14页
目的光敏剂被特定波长的光激发后,产生的活性氧类能破坏细胞组织,介导细胞死亡,对微生物感染、肿瘤等相关疾病的治疗具有重要意义。方法基于粳稻类向光素1B(Oryza sativa japonica phototropin-1B-like)的LOV(lightoxygen-voltage)结构... 目的光敏剂被特定波长的光激发后,产生的活性氧类能破坏细胞组织,介导细胞死亡,对微生物感染、肿瘤等相关疾病的治疗具有重要意义。方法基于粳稻类向光素1B(Oryza sativa japonica phototropin-1B-like)的LOV(lightoxygen-voltage)结构域,设计得到光敏剂LovPSO2及其突变体LovPRO2。在445 nm、70μmol·m^(-2)·s^(-1)蓝光照射下,每隔2 min测量LovPSO2和LovPRO2的单线态氧产量,持续10 min,每隔1 min测量其超氧阴离子产量,持续5 min,并研究温度、光照对其稳定性的影响,最后将其转入E.coli BL21(DE3)和HeLa细胞中表达并分析光毒性效果。结果在445 nm、70μmol·m^(-2)·s^(-1)蓝光照射下,LovPSO2是一种能产生大量单线态氧的Ⅱ型光敏剂(ΦΔ=0.61),LovPRO2是一种能够同时产生单线态氧和超氧阴离子的光敏剂。蛋白质稳定性分析结果表明,LovPSO2和LovPRO2具有较好的温度稳定性,其中LovPRO2的光稳定性更好。蛋白质的光毒性分析结果表明,445 nm、30 mW/cm^(2)蓝光照射30 min后,LovPSO2和LovPRO2对E.coli BL21(DE3)菌株有较好的光毒性,致死率高达90%。结论LovPSO2和LovPRO2可作为抗菌光敏剂,在食品和医疗等方面均有较为广阔的应用前景。 展开更多
关键词 光敏剂 活性氧类 单线态氧 超氧阴离子
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Ru⁃doped Co_(3)O_(4)/reduced graphene oxide:Preparation and electrocatalytic oxygen evolution property
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作者 TIAN Tian ZHOU Meng +5 位作者 WEI Jiale LIU Yize MO Yifan YE Yuhan JIA Wenzhi HE Bin 《无机化学学报》 北大核心 2025年第2期385-394,共10页
Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then... Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then Ru3+was introduced for ion exchange,and the porous Ru-doped Co_(3)O_(4)/rGO(Ru-Co_(3)O_(4)/rGO)composite electrocatalyst was prepared by annealing.The phase structure,morphology,and valence state of the catalyst were analyzed by X-ray powder diffraction(XRD),scanning electron microscope(SEM),transmission electron microscopy(TEM),and X-ray photoelectron spectroscopy(XPS).In 1 mol·L^(-1)KOH,the oxygen evolution reaction(OER)performance of the catalyst was measured by linear sweep voltammetry,cyclic voltammetry,and chronoamperometry.The results show that the combination of Ru doping and rGO provides a fast channel for collaborative electron transfer.At the same time,rGO as a carbon carrier can improve the electrical conductivity of Ru-Co_(3)O_(4)particles,and the uniformly dispersed nanoparticles enable the reactants to diffuse freely on the catalyst.The results showed that the electrochemical performance of Ru-Co_(3)O_(4)/rGO was much better than that of Co_(3)O_(4)/rGO,and the overpotential of Ru-Co_(3)O_(4)/rGO was 363.5 mV at the current density of 50 mA·cm^(-2). 展开更多
关键词 metal-organic framework GRAPHENE ELECTROCATALYST oxygen evolution reaction
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Ordering Degree Regulation of Pt_(2)NiCo Intermetallics for Efficient Oxygen Reduction Reaction
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作者 Chen-Hao Zhang Han-Yu Hu +3 位作者 Jun-Hao Yang Qian Zhang Chang Yang De-Li Wang 《电化学(中英文)》 北大核心 2025年第4期12-23,共12页
Alloying transition metals with Pt is an effective strategy for optimizing Pt-based catalysts toward the oxygen reduction reaction(ORR).Atomic ordered intermetallic compounds(IMC)provide unique electronic and geometri... Alloying transition metals with Pt is an effective strategy for optimizing Pt-based catalysts toward the oxygen reduction reaction(ORR).Atomic ordered intermetallic compounds(IMC)provide unique electronic and geometrical effects as well as stronger intermetallic interactions due to the ordered arrangement of metal atoms,thus exhibiting superior electrocata-lytic activity and durability.However,quantitatively analyzing the ordering degree of IMC and exploring the correlation between the ordering degree and ORR activity remains extremely challenging.Herein,a series of ternary Pt_(2)NiCo interme-tallic catalysts(o-Pt_(2)NiCo)with different ordering degree were synthesized by annealing temperature modulation.Among them,the o-Pt_(2)NiCo which annealed at 800℃for two hours exhibits the highest ordering degree and the optimal ORR ac-tivity,which the mass activity of o-Pt_(2)NiCo is 1.8 times and 2.8 times higher than that of disordered Pt_(2)NiCo alloy and Pt/C.Furthermore,the o-Pt_(2)NiCo still maintains 70.8%mass activity after 30,000 potential cycles.Additionally,the ORR activity test results for Pt_(2)NiCo IMC with different ordering degree also provide a positive correlation between the ordering degree and ORR activity.This work provides a prospective design direction for ternary Pt-based electrocatalysts. 展开更多
关键词 Fuel cell oxygen reduction reaction ELECTROCATALYSIS Intermetallic compound Ordering degree
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A CNT Intercalated Co Porphyrin-Based Metal Organic Framework Catalyst for Oxygen Reduction Reaction
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作者 Pei-Pei He Jin-Hua Shi +6 位作者 Xiao-Yu Li Ming-Jie Liu Zhou Fang Jing He Zhong-Jian Li Xin-Sheng Peng Qing-Gang He 《电化学(中英文)》 北大核心 2025年第1期31-40,共10页
The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNT... The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNTs)during the growth process of MOF crystals,synthesizing a metalloporphyrin-based MOF catalyst TCPPCo-MOF-CNT with a unique CNT-intercalated MOF structure.Physical characterization revealed that the CNTs enhance the overall conductivity while retaining the original characteristics of the MOF and metalloporphyrin.Simultaneously,the insertion of CNTs generated adequate mesopores and created a hierarchical porous structure that enhances mass transfer efficiency.X-ray photoelectron spectroscopic analysis confirmed that the C atom in CNT changed the electron cloud density on the catalytic active center Co,optimizing the electronic structure.Consequently,the E_(1/2) of the TCPPCo-MOF-CNT catalyst under neutral conditions reached 0.77 V(vs.RHE),outperforming the catalyst without CNTs.When the TCPPCo-MOF-CNT was employed as the cathode catalyst in assembling microbial fuel cells(MFCs)with Nafion-117 as the proton exchange membrane,the maxi-mum power density of MFCs reached approximately 500 mW·m^(-2). 展开更多
关键词 Metal organic framework CNT intercalated ELECTROCATALYSIS oxygen reduction reaction Microbial fuel cell
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Theoretical Insights into the Atomic and Electronic Structures of Polyperyleneimide:On the Origin of Photocatalytic Oxygen Evolution Activity
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作者 Yi-Qing Wang Zhi Lin +1 位作者 Ming-Tao Li Shao-Hua Shen 《电化学(中英文)》 北大核心 2025年第5期28-36,共9页
Polymeric perylene diimide(PDI)has been evidenced as a good candidate for photocatalytic water oxidation,yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration.Her... Polymeric perylene diimide(PDI)has been evidenced as a good candidate for photocatalytic water oxidation,yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration.Herein,with crystal and atomic structures of the self-assembled PDI revealed from the X-ray diffraction pattern,the electronic structure is theoretically illustrated by the first-principles density functional theory calculations,suggesting the suitable band structure and the direct electronic transition for efficient photocatalytic oxygen evolution over PDI.It is confirmed that the carbonyl O atoms on the conjugation structure serve as the active sites for oxygen evolution reaction by the crystal orbital Hamiltonian group analysis.The calculations of reaction free energy changes indicate that the oxygen evolution reaction should follow the reaction pathway of H_(2)O→^(*)OH→^(*)O→^(*)OOH→^(*)O_(2)with an overpotential of 0.81 V.Through an in-depth theoretical computational analysis in the atomic and electronic structures,the origin of photocatalytic oxygen evolution activity for PDI is well illustrated,which would help the rational design and modification of polymeric photocatalysts for efficient oxygen evolution. 展开更多
关键词 Photocatalytic oxygen evolution Polymeric perylene diimide Atomic structure Electronic structure Reaction pathway
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Metal-organic framework-derived sulfur-doped iron-cobalt tannate nanorods for efficient oxygen evolution reaction performance
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作者 ZHAI Haoying WEN Lanzong +3 位作者 LIAO Wenjie LI Qin ZHOU Wenjun CAO Kun 《无机化学学报》 北大核心 2025年第5期1037-1048,共12页
Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nano... Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance. 展开更多
关键词 hydrothermal method tannic acid metal‑organic framework ELECTROCATALYSIS oxygen evolution reaction
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The reactivity of CO with different lattice oxygens on Cu doped CeO_(2)(111):A DFT study
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作者 LI Yuan ZHENG Yisong +6 位作者 WANG Hao WANG Honghao ZHANG Caishun HU Shaozheng HAN Jiao ZHANG Lei GAO Zhixian 《燃料化学学报(中英文)》 北大核心 2025年第6期906-917,共12页
The adsorption of CO on different lattice oxygen sites in Cu doped CeO_(2)(111)was studied by DFT method,and the geometrical structure and electronic properties of adsorption systems were analyzed.The results showed t... The adsorption of CO on different lattice oxygen sites in Cu doped CeO_(2)(111)was studied by DFT method,and the geometrical structure and electronic properties of adsorption systems were analyzed.The results showed that CO interacted with lattice oxygen on the first layer formed CO_(2).However,when adsorbed on the second layer lattice oxygen,carbonate species were formed with the participation of first layer lattice oxygens,i.e.,CO co-adsorbed on first and second layer lattice oxygens.For the second layer adsorption,the absolute CO adsorption energy was big on the Oss nearby Cu.This kind of carbonates was thermodynamically stable,and it was attributed to the facilitation of Cu on CO adsorption,manifested by an electron migration behavior from the C 2p orbitals to the Cu 3d orbitals.However,the absolute CO adsorption energy on the Oss away from Cu was small.Compared to the formation of carbonates,the formation CO_(2)had very small absolute adsorption energy,suggesting the formed carbonates on second layer was stable.Further,when CO adsorbed on the systems with a carbonate,the absolute CO adsorption energy was significantly smaller than that of the non-carbonated system,indicating that the formation of carbonates inhibited CO oxidation on Cu/CeO_(2)(111).Therefore,the formation of carbonates was unfavorable for CO oxidation reaction on Cu/CeO_(2)(111).The results of this study provide theoretical support for the negative effect of CO_(2)on ceria-based catalysts. 展开更多
关键词 Cu/CeO_(2)(111) CO adsorption CARBONATE lattice oxygen
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Effects of the oxygen transport properties of electrolytes on the reaction mechanisms in lithium-oxygen batteries
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作者 Aijing Yan Zhuojun Zhang +1 位作者 Xu Xiao Peng Tan 《中国科学技术大学学报》 北大核心 2025年第2期35-42,34,I0001,I0002,共11页
Lithium-oxygen batteries attract considerable attention due to exceptionally high theoretical energy density,while the development remains in its early stage.As is widely suggested,the solution mechanism induces great... Lithium-oxygen batteries attract considerable attention due to exceptionally high theoretical energy density,while the development remains in its early stage.As is widely suggested,the solution mechanism induces greater discharge capacity,while the surface mechanism induces greater cycle stability.Therefore,battery performance can be improved by adjusting the reaction mechanism.Previous studies predominantly focus on extremely thin or flat electrodes.In contrast,this work utilizes thick electrodes,emphasizing the importance of mass transport.Given that the electrolyte solvent is the main site of mass transport,the effects of two typical solvents on mass transport and battery performance are investigated:dimethyl sulfoxide with low viscosity and a high O_(2) diffusion rate and tetraethylene glycol dimethyl ether with high O_(2) solubility and high Li+transport capability.The results reveal a novel pathway for reaction mechanism induction where the mechanism varies with the spatial position of the electrode.As the spatial distribution of the electrode progresses,a layered appearance of solution mechanism products,transition state products,and surface mechanism products emerges,which is attributed to the increase in the mass transfer resistance.This work presents a distinct perspective on the way solvents influence reaction pathways and offers a new approach to regulating reaction pathways. 展开更多
关键词 Li-O_(2)battery nonaqueous electrolyte oxygen transport property solution mechanism surface mechanism
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De novo-design of highly exposed Co−N−C single-atom catalyst for oxygen reduction reaction
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作者 ZHOU Dan ZHU Hongyue +1 位作者 ZHAO Yang LIU Yiming 《燃料化学学报(中英文)》 北大核心 2025年第1期128-137,共10页
The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these c... The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these catalysts were buried in the carbon matrix,resulting in a low metal utilization and inaccessibility for adsorption of reactants during the catalytic process.Herein,we reported a facile synthesis based on the hard-soft acid-base(HSAB)theory to fabricate Co single-atom catalysts with highly exposed metal atoms ligated to the external pyridinic-N sites of a nitrogen-doped carbon support.Benefiting from the highly accessible Co active sites,the prepared Co−N−C SAC exhibited a superior oxygen reduction reactivity comparable to that of the commercial Pt/C catalyst,showing a high turnover frequency(TOF)of 0.93 e^(−)·s^(-1)·site^(-1)at 0.85 V vs.RHE,far exceeding those of some representative SACs with a ultra-high metal content.This work provides a rational strategy to design and prepare M−N−C single-atom catalysts featured with high site-accessibility and site-density. 展开更多
关键词 hard-soft acid-base Co−N−C single-atom catalyst highly accessible active sites oxygen reduction reaction
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Ionic Liquid Enhanced Proton Transfer for Neutral Oxygen Evolution Reaction
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作者 Ming-Xing Chen Nian Liu +2 位作者 Zi-He Du Jing Qi Rui Cao 《电化学(中英文)》 北大核心 2025年第7期27-36,共10页
The development of highly active catalyst in pH-neutral media for oxygen evolution reaction(OER)is critical in the field of renewable energy storage and conversion.Nevertheless,the slow kinetics of proton-coupled elec... The development of highly active catalyst in pH-neutral media for oxygen evolution reaction(OER)is critical in the field of renewable energy storage and conversion.Nevertheless,the slow kinetics of proton-coupled electron transfer(PCET)hinders the overall OER efficiency.Herein,we report an ionic liquid(IL)modified CoSn(OH)_(6)nanocubes(denoted as CoS-n(OH)_(6)-IL),which could be prepared through a facile strategy.The modified IL would not change the structural character-istics of CoSn(OH)_(6),but could effectively regulate the local proton activity near the active sites.The CoSn(OH)_(6)-IL exhibited higher intrinsic OER performances than the pristine CoSn(OH)_(6)in neutral media.For example,the current density of CoS-n(OH)_(6)-IL at 1.8 V versus reversible hydrogen electrode(RHE)was about 4 times higher than that of CoSn(OH)_(6).According to the pH-dependent kinetic investigations,operando electrochemical impedance spectroscopic,chemical probe tests,and deuterium kinetic isotope effects,the interfacial layer of IL could be utilized as a proton transfer mediator to promote the proton transfer,which enhances the surface coverage of OER intermediates and reduces the activation barrier.Consequent-ly,the sluggish OER kinetics would be efficiently accelerated.This study provides a facile and effective strategy to facilitate the PCET processes and is beneficial to guide the rational design of OER electrocatalysts. 展开更多
关键词 ELECTROCATALYSIS oxygen evolution reaction Ionic liquid Proton transfer CoSn(OH)_(6)nanocube
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Biomass-derived N-doped porous carbon supported single Fe atoms as low-cost and high-performance electrocatalysts for oxygen reduction reaction
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作者 WANG Li-ping XIAO Jin +1 位作者 MAO Qiu-yun ZHONG Qi-fan 《Journal of Central South University》 2025年第4期1368-1383,共16页
Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and exp... Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and expensive reagents used,the cost of SACs is usually too high to put into practical application.The development of cost-effective and sustainable SACs remains a great challenge.Herein,a low-cost method employing biomass is designed to prepare efficient single-atom Fe-N-C catalysts(SA-Fe-N-C).Benefiting from the confinement effect of porous carbon support and the coordination effect of glucose,SA-Fe-N-C is derived from cheap flour by the two-step pyrolysis.Atomically dispersed Fe atoms exist in the form of Fe-N_(x),which acts as active sites for ORR.The catalyst shows outstanding activity with a half-wave potential(E_(1/2))of 0.86 V,which is better than that of Pt/C(0.84 V).Additionally,the catalyst also exhibits superior stability.The ORR catalyzed by SA-Fe-N-C proceeds via an efficient 4e transfer pathway.The high performance of SA-Fe-N-C also benefits from its porous structure,extremely high specific surface area(1450.1 m^(2)/g),and abundant micropores,which are conducive to increasing the density of active sites and fully exposing them.This work provides a cost-effective strategy to synthesize SACs from cheap biomass,achieving a balance between performance and cost. 展开更多
关键词 oxygen reduction reaction single-atom catalyst porous carbon MICROPORE biomass
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Modeling and analysis of a novel oxygen production approach with full-spectrum solar energy for the lunar human base
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作者 Wei Zhu Maobin Hu 《中国科学技术大学学报》 北大核心 2025年第2期2-17,1,I0001,共18页
Building a lunar human base is one of the important goals of human lunar exploration.This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temper... Building a lunar human base is one of the important goals of human lunar exploration.This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temperature carbon dioxide electrolysis,utilizing the full solar spectrum.The optimal oxygen production rates under different solid oxide electrolysis cell inlet temperatures T_(e),ultraviolet(UV)separation wavelengths λ_(2),infrared(IR)separation wavelengths,and photovoltaic cell materials were explored.The results indicate that the inlet temperature of the solid oxide electrolysis cell should be as high as possible so that more carbon dioxide can be converted into carbon monoxide and oxygen.Furthermore,when the ultraviolet separation wavelength is approximately 385 nm,the proportion of solar energy allocated to the photoreaction and electrolysis cell is optimal,and the oxygen production rate is highest at 2.754×10^(-4) mol/s.Moreover,the infrared separation wavelength should be increased as much as possible within the allowable range to increase the amount of solar radiation allocated to the electrolysis cell to improve the rate of oxygen generation.In addition,copper indium gallium selenide(CIGS)has a relatively large separation wavelength,which can result in a high oxygen production rate of 3.560×10^(-4) mol/s.The proposed integrated oxygen production method can provide a feasible solution for supplying oxygen to a lunar human base. 展开更多
关键词 lunar oxygen production full-spectrum solar energy photovoltaic and photon-enhanced thermionic emission electrolysis of carbon dioxide photothermal synergistic reaction solid oxide electrolysis cell
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Numerical study on flow characteristics of large copper smelting bottom-blown furnace under strong and weak coupling oxygen supply
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作者 JIANG Bao-cheng GUO Xue-yi +1 位作者 WANG Song-song WANG Qin-meng 《Journal of Central South University》 2025年第2期363-375,共13页
The melt stirring in a large copper smelting oxygen bottom-blown furnace is caused by the large amount of gas movement blown in by two rows of oxygen lances.At present,the two rows of oxygen lances provide oxygen of e... The melt stirring in a large copper smelting oxygen bottom-blown furnace is caused by the large amount of gas movement blown in by two rows of oxygen lances.At present,the two rows of oxygen lances provide oxygen of equal strength,and the stirring in the central area of the melt is insufficient,which restricts the efficient progress of the smelting reaction.This study proposes a strong-weak coupling oxygen supply method and establishes an equivalent model based on a large bottom-blown furnace(LBBF)of an enterprise to simulate the bubble characteristics and flow characteristics of the molten pool.The results show that adjusting the flow ratio between the two rows of oxygen lances can create a“strong”and a“weak”coexisting source of disturbance in an LBBF.It is worth noting that when the flow rate ratio of the two rows of oxygen lances is 1.6,the peak velocity generated by the“strong”distur bance source in the molten pool increases by 18.92%,and the disturbance range increases.This method effectively strengthens the stirring in the central area of the molten pool,improves smelting efficiency,and does not produce harmful melt splashes.It provides important guidance for optimizing production practice. 展开更多
关键词 large bottom-blown furnace oxygen supply flow characteristics initial bubbles
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Co-enhancement of doped N and oxygen vacancies on the photocatalytic performance of ceria:Mechanism and influence of crystal faces
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作者 WANG Fan LI Jun-qi +3 位作者 MURALI Arun CHEN Chao-yi ZHANG Wei LAN Yuan-pei 《Journal of Central South University》 2025年第6期2129-2147,共19页
Nitrogen doping has significant effects on the photocatalytic performance of ceria(CeO_(2)),and the possible synergistic effect with the inevitably introduced abundant oxygen vacancies(OVs)is of great significance for... Nitrogen doping has significant effects on the photocatalytic performance of ceria(CeO_(2)),and the possible synergistic effect with the inevitably introduced abundant oxygen vacancies(OVs)is of great significance for further investigation,and the specifically exposed crystal faces of CeO_(2)may have an impact on the performance of nitrogen doped CeO_(2).Herein,nitrogen-doped CeO_(2)with different morphologies and exposed crystal faces was prepared,and its performances in the photocatalytic degradation of tetracycline(TC)or hydrogen production via water splitting were evaluated.Density functional theory(DFT)was used to simulate the band structures,density of states,and oxygen defect properties of different CeO_(2)structures.It was found that nitrogen doping and OVs synergistically promoted the catalytic activity of nitrogen-doped CeO_(2).In addition,the exposed crystal faces of CeO_(2)have significant effects on the introduction of nitrogen and the ease of OV generation,as well as the synergistic effect of nitrogen doping with OVs.Among them,the rod-like nitrogen-doped CeO_(2)with exposed(110)face(R-CeO_(2)-NH_(3))showed a photocatalytic degradation ratio of 73.59%for TC and hydrogen production of 156.89μmol/g,outperforming other prepared photocatalysts. 展开更多
关键词 nitrogen doping CeO 2 oxygen vacancies synergistic effect crystal faces PHOTOCATALYSIS
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Taming of trinitromethyl-oxadiazole to access high density and high oxygen balance via a dual modulation strategy
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作者 Jinya Zhang Teng Fei +4 位作者 Jingwei Meng Jinxiong Cai Lei Zhang Siping Pang Chunlin He 《Defence Technology(防务技术)》 2025年第1期142-149,共8页
Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense oxidizers.In this work,an effective dual modulation strategy involv... Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense oxidizers.In this work,an effective dual modulation strategy involving both molecular isomerization and crystal morphology control was employed to design and optimize trinitromethyl-oxadiazole with improved comprehensive performance.Utilizing this dual strategy,3,5-bis(trinitromethyl)-1,2,4-oxadiazole(3)was synthesized,resulting in the formation of two distinct crystal morphologies(needle and sheet)corresponding to two crystal forms(3-a and3-b).Encouragingly,while maintaining ultra-high oxygen balance(21.73%),3 achieves impressive densities(1.97-1.98 g/cm^(3)).To our knowledge,the density of 1.98 g/cm^(3)for 3-a sets a new record among that of nitrogen-rich monocyclic compounds.Notably,practical crystal morphology prediction was creatively introduced to guide the experimental crystallization conditions of 3,increasing the impact sensitivity and friction sensitivity from 1 J to 80 N(3-a)to 10 J and 240 N(3-b),respectively.Additionally,the crystal structural analyses and theoretical calculations were conducted to elucidate the reasons of differences between 3-a and 3-b in density and stability.This work provides an efficient strategy to enhance performance of trinitromethyl derivatives,broadening the path and expanding the toolbox for energetic materials. 展开更多
关键词 Energetic materials High oxygen balance High density Dual modulation Trinitromethyl group
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Series Reports from Professor Wei's Group of Chongqing University:Advancements in Electrochemical Energy Conversions(1/4):Report 1:High-performance Oxygen Reduction Catalysts for Fuel Cells 被引量:1
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作者 Fa-Dong Chen Zhuo-Yang Xie +5 位作者 Meng-Ting Li Si-Guo Chen Wei Ding Li Li Jing Li Zi-Dong Wei 《电化学(中英文)》 CAS 北大核心 2024年第7期1-27,共27页
Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without lo... Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without losses of activity and durability,and their research advances in this area over the past three decades are briefly reviewed herein.Regarding the Pt-based catalysts and the low Pt usage,they have firstly tried to clarify the degradation mechanism of Pt/C catalysts,and then demonstrated that the activity and stability could be improved by three strategies:regulating the nanostructures of the active sites,enhancing the effects of support materials,and optimizing structures of the three-phase boundary.For Pt-free catalysts,especialiy carbon-based ones,several strategies that they proposed to enhance the activity of nitrogen-/heteroatom-doped carbon catalysts are firstly presented.Then,an indepth understanding of the degradation mechanism for carbon-based catalysts is discussed,and followed by the corresponding stability enhancement strategies.Also,the carbon-based electrode at the micrometer-scale,faces the challenges such as low active-site density,thick catalytic layer,and the effect of hydrogen peroxide,which require rational structure design for the integral cathodic electrode.This review finally gives a brief conclusion and outlook about the low cost and long lifespan of cathodic oxygen reduction catalysts. 展开更多
关键词 Fuel cell oxygen reduction reaction Pt-based catalyst Carbon-based catalyst
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A carbon material doped with both porous FeO_(x) and N as an efficient catalyst for oxygen reduction reactions
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作者 GAO Jian WANG Xin-yao +4 位作者 MENG Ling-xin YIN Zhen MA Na TAN Xiao-yao ZHANG Peng 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第6期1202-1212,共11页
To replace precious metal oxygen reduction reaction(ORR)electrocatalysts,many transition metals and N-doped car-bon composites have been proposed in the last decade resulting in their rapid development as promising no... To replace precious metal oxygen reduction reaction(ORR)electrocatalysts,many transition metals and N-doped car-bon composites have been proposed in the last decade resulting in their rapid development as promising non-precious metal catalysts.We used Ketjenblack carbon as the precursor and mixed it with a polymeric ionic liquid(PIL)of[Hvim]NO_(3) and Fe(NO_(3))_(3),which was thermally calcined at 900℃ to produce a porous FeO_(x),N co-doped carbon material denoted FeO_(x)-N/C.Because the PIL of[Hvim]NO_(3) strongly combines with and disperses Fe^(3+)ions,and NO_(3)−is thermally pyrolyzed to form the porous structure,the FeO_(x)-N/C catalyst has a high electrocatalytic activity for the ORR in both 0.1 mol L^(−1) KOH and 0.5 mol L^(−1) H_(2)SO_(4) electrolytes.It was used as the catalyst to assemble a zinc-air battery,which had a peak power density of 185 mW·cm^(−2).Its superior electrocatalytic activity,wide pH range,and easy preparation make FeO_(x)-N/C a promising electrocatalyst for fuel cells and metal-air batteries. 展开更多
关键词 oxygen reduction reaction Ionic liquid Porous carbon ELECTROCATALYSIS FeOx N co-doping
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Oxygen vacancy induced carrier mobility enhancement in nano-multilayered ZrO_(2):Y_(2)O_(3)/SrTiO_(3) thin films for non-volatile memory devices
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作者 YANG Ze-ou HUANG Xiao-zhong +3 位作者 HU Hai-long MA Bing-yang SHANG Hai-long YUE Jian-ling 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3674-3687,共14页
The influence of oxygen vacancy-dominated carrier mobility on the performance of memristors has attractedconsiderable attention.The device’s carrier mobility can be significantly improved by forming a nano-multilayer... The influence of oxygen vacancy-dominated carrier mobility on the performance of memristors has attractedconsiderable attention.The device’s carrier mobility can be significantly improved by forming a nano-multilayeredheterostructure when the individual layer thickness is below a critical value.In this work,Pt/[ZrO_(2):Y_(2)O_(3)(YSZ)/SrTiO_(3)(STO)]n/Nb:SrTiO_(3)(NSTO)memristive devices were configurated through laser pulse deposited YSZ/STO nanomultilayeredactive layer with both Pt and NSTO acting as top and counter electrodes.Specifically,the Pt/[YSZ/STO]5/NSTO device with five consecutive layers of YSZ/STO thin film shows superior memristor performance,and itscorresponding carrier mobility presents a significantly enhanced value compared to that of other periodic numbers ofYSZ/STO composed memristive devices.This can be attributed to the increase of oxygen vacancy concentration in thedevice,as evidenced by both experimental results and theoretical analysis.This work provides a significant approach inimproving the performance of memristor dominated by oxygen vacancy transporting mechanism. 展开更多
关键词 YSZ/STO nano-multilayered thin film MEMRISTOR oxygen vacancy carrier mobility
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High-performance Ni-Co-Mn electrocatalyst recovered from spent lithium-ion battery cathode materials for robust oxygen evolution in acid solution
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作者 JIANG Liang-xing FAN Yao-jian +2 位作者 LIU Fang-yang ZHANG Zong-liang WANG Jun 《Journal of Central South University》 CSCD 2024年第12期4472-4482,共11页
Recovering valuable metals from spent lithium-ion batteries(LIBs)for high value-added application is beneficial for global energy cycling and environmental protection.In this work,we obtain the high-performance N-dope... Recovering valuable metals from spent lithium-ion batteries(LIBs)for high value-added application is beneficial for global energy cycling and environmental protection.In this work,we obtain the high-performance N-doped Ni-Co-Mn(N-NCM)electrocatalyst from waste LIBs,for robust oxygen evolution application.Lithium-rich solution and NCM oxides are effectively separated from ternary cathode materials by sulfation roasting and low-temperature water leaching approach,in which the recovery efficiency of Li metal reaches nearly 100%.By facile NH_(3)treatment,the incorporation of N into NCM significantly increases the ratio of low-valence state Co^(2+)and Mn^(2+),and the formed Mn-N bond benefits the surface catalytic kinetics.Meanwhile,the N doping induces lattice expansion of the NCM,triggering tensile stress to favor the adsorption of the reactant.Thus,the optimized N-NCM electrocatalyst exhibits the superior overpotentials of 256 and 453 mV to achieve the current density of 10 and 100 mA/cm^(2),respectively,with a low Tafel slope of 37.3 mV/dec.This work provides a fresh avenue for recycling spent LIBs in the future to achieve sustainable development. 展开更多
关键词 recovered Ni-Co-Mn oxides N doping oxygen evolution electrocatalyst spent ternary lithium-ion batteries
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