电化学分解水制氢是实现可持续、绿色制氢的重要途径,但由于阳极析氧反应(OER)缓慢的反应速率严重阻碍了全水解的效率。为从根本上解决此问题,利用低理论电位的硫离子氧化反应(SOR)取代OER,能极大的降低水电解的电压,提升水解效率,同时...电化学分解水制氢是实现可持续、绿色制氢的重要途径,但由于阳极析氧反应(OER)缓慢的反应速率严重阻碍了全水解的效率。为从根本上解决此问题,利用低理论电位的硫离子氧化反应(SOR)取代OER,能极大的降低水电解的电压,提升水解效率,同时在阳极获得增值产物。本工作通过共沉淀法成功制备出六氰钴酸钴(CoHCC)材料,并将CoHCC负载到泡沫镍(NF)基底上制备工作电极(CoHCC/NF),作为高效的硫离子氧化反应催化剂。在三电极体系下测试其SOR催化性能,CoHCC/NF仅需要0.31 V vs.RHE的低电压就能达到100 mA·cm^(-2)的电流密度,这远优于Co(OH)_(2)/NF和NF。此外,CoHCC/NF有最低的Tafel斜率(77mA·dec^(-1))和最小的电化学阻抗,且表现出良好的稳定性。同时,在两电极体系下模拟实际电解水制氢,测试表明新型耦合反应系统(SOR-HER)在达到100 mA·cm^(-2)电流密度时所需的电压远低于传统的全水解(OER-HER)制氢系统,本工作为超低能耗制氢和硫回收提供了一条有吸引力的途径。展开更多
本文通过微波法超快速制备了泡沫镍(NF)负载的Co/Zn复合氧化物(Co-Zn/NF)。XRD测试表明生成的Co/Zn复合氧化物具有低结晶度。采用线性扫描伏安法(LSV)测试了Co-Zn/NF在碱性条件下的电催化硫离子氧化性能。与泡沫镍负载的单金属氧化物(Co...本文通过微波法超快速制备了泡沫镍(NF)负载的Co/Zn复合氧化物(Co-Zn/NF)。XRD测试表明生成的Co/Zn复合氧化物具有低结晶度。采用线性扫描伏安法(LSV)测试了Co-Zn/NF在碱性条件下的电催化硫离子氧化性能。与泡沫镍负载的单金属氧化物(Co/NF和Zn/NF)相比,Co-Zn/NF表现出更好的催化性能。在含有1 mol·L^(-1)Na2S和1 mol·L^(-1)NaOH的电解液中,Co-Zn/NF达到100 m A·cm^(-2)的电流密度所需的电位仅为0.28 V vs RHE,并且在恒定100 m A·cm^(-2)的电流密度下,长时间工作35小时后仍保持高的催化性能。此外,组装非对称电解槽(阳极:硫离子氧化反应(sulfion oxidation reaction,SOR)用1 mol·L^(-1)Na2S和1mol·L^(-1)NaOH为电解质,阴极:析氢反应(hydrogen evolution reaction,HER)用1 mol·L^(-1)Na OH为电解质)进行双电极硫氧化辅助电解水制氢测试,与传统的碱性电解水相比,达到100 m A·cm^(-2)电流密度所需的能耗降低了46%。本工作为低能耗电化学制氢提供了一种新思路,并证明了SOR耦合HER电解水制氢具有实际应用的可行性。展开更多
电解水是可持续绿色制氢的重要方法,但阳极缓慢的析氧反应(OER)严重阻碍电解水能量转化效率的提升,利用氧化电位较低的硫离子氧化反应(SOR)替代OER与阴极析氢反应耦合可以实现能耗的大幅降低。本文通过共沉淀法成功制备了一种钴基沸石...电解水是可持续绿色制氢的重要方法,但阳极缓慢的析氧反应(OER)严重阻碍电解水能量转化效率的提升,利用氧化电位较低的硫离子氧化反应(SOR)替代OER与阴极析氢反应耦合可以实现能耗的大幅降低。本文通过共沉淀法成功制备了一种钴基沸石咪唑酯骨架材料(ZIF-67),通过XRD、SEM、XPS测试手段对催化材料进行了物相分析,结果表明制备的ZIF-67催化材料由许多堆积在一起的立方体纳米颗粒组成。在三电极体系中对其进行SOR催化性能测试,将ZIF-67涂敷在泡沫镍基底上作为工作电极(ZIF-67/NF),ZIF-67/NF仅需0.361 V vs.RHE的电压就可以达到50 mA·cm^(-2)的电流密度,其电催化活性远优于Co(OH)2/NF和NF。ZIF-67/NF还表现出最低的Tafel斜率(73 mA·dec^(-1))和最小的电化学阻抗,并展现出良好的稳定性。此外,对基于SOR的两电极耦合制氢体系的电化学性能进行了测试,发现所需施加电压远小于传统的全水解制氢系统,为超低能耗制氢提供一种切实可行的方案。展开更多
In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynami...In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynamics of PbSO4 was calculated by software HSC 5.0. The effects of gas concentration, reaction temperature, time and mass of sample on reduction of PbSO4 were examined by thermogravimetry(TG) and XRD. Roasting tests further verify the conclusions of thermodynamic and TG analyses. The results show that increasing temperature in the reasonable range and CO content are favorable for the formation of Pb S. The reduction process is controlled by chemical reaction and calculation value of the activation energy is 47.88 k J/mol.展开更多
The leaching kinetics of molybdenum from Ni-Mo ore in sulfuric acid solution with sodium peroxodisulfate was studied.The effects including leaching temperature, reaction time, particle size, stirring speed, and concen...The leaching kinetics of molybdenum from Ni-Mo ore in sulfuric acid solution with sodium peroxodisulfate was studied.The effects including leaching temperature, reaction time, particle size, stirring speed, and concentrations of sulfuric acid and sodium peroxodisulfate were investigated. The leaching process of molybdenum from Ni-Mo ore is controlled by the chemical reaction through the solid layer across the unreacted shrinking core. The apparent activation energy of the leaching of molybdenum is calculated to be 41.0 k J/mol and the leaching kinetics equation of molybdenum from Ni-Mo ore is expressed as1-(1-a)1/3=3405.7exp[-41030.0/(RT)]t.展开更多
Electrochimcal behaviors of rusticyanin （Rus.） isolated from Acidithiobacillus ferrooxidans were investigated through Rus.-ZnS-QDs/L-Cys/Au electrode. The cyclic voltammetric results indicate that rusticyanin immobi...Electrochimcal behaviors of rusticyanin （Rus.） isolated from Acidithiobacillus ferrooxidans were investigated through Rus.-ZnS-QDs/L-Cys/Au electrode. The cyclic voltammetric results indicate that rusticyanin immobilized on the surface of Rus.-ZnS-QDs/L-Cys/Au electrode can undergo a direct quasi-reversible electrochemical reaction. The immobilized rusticyanin is not denatured and still retains its activity in the temperature range of 19-43 ℃. The reduction ability of the protein increases and its oxidation ability becomes weak with the increase of pH from 6.0 to 7.8. Fe^2＋ ions in the solution can promote the electron transfer kinetics of the immobilized rusticyanin and make its peak potentials （φp） markedly move negatively.展开更多
文摘电化学分解水制氢是实现可持续、绿色制氢的重要途径,但由于阳极析氧反应(OER)缓慢的反应速率严重阻碍了全水解的效率。为从根本上解决此问题,利用低理论电位的硫离子氧化反应(SOR)取代OER,能极大的降低水电解的电压,提升水解效率,同时在阳极获得增值产物。本工作通过共沉淀法成功制备出六氰钴酸钴(CoHCC)材料,并将CoHCC负载到泡沫镍(NF)基底上制备工作电极(CoHCC/NF),作为高效的硫离子氧化反应催化剂。在三电极体系下测试其SOR催化性能,CoHCC/NF仅需要0.31 V vs.RHE的低电压就能达到100 mA·cm^(-2)的电流密度,这远优于Co(OH)_(2)/NF和NF。此外,CoHCC/NF有最低的Tafel斜率(77mA·dec^(-1))和最小的电化学阻抗,且表现出良好的稳定性。同时,在两电极体系下模拟实际电解水制氢,测试表明新型耦合反应系统(SOR-HER)在达到100 mA·cm^(-2)电流密度时所需的电压远低于传统的全水解(OER-HER)制氢系统,本工作为超低能耗制氢和硫回收提供了一条有吸引力的途径。
文摘本文通过微波法超快速制备了泡沫镍(NF)负载的Co/Zn复合氧化物(Co-Zn/NF)。XRD测试表明生成的Co/Zn复合氧化物具有低结晶度。采用线性扫描伏安法(LSV)测试了Co-Zn/NF在碱性条件下的电催化硫离子氧化性能。与泡沫镍负载的单金属氧化物(Co/NF和Zn/NF)相比,Co-Zn/NF表现出更好的催化性能。在含有1 mol·L^(-1)Na2S和1 mol·L^(-1)NaOH的电解液中,Co-Zn/NF达到100 m A·cm^(-2)的电流密度所需的电位仅为0.28 V vs RHE,并且在恒定100 m A·cm^(-2)的电流密度下,长时间工作35小时后仍保持高的催化性能。此外,组装非对称电解槽(阳极:硫离子氧化反应(sulfion oxidation reaction,SOR)用1 mol·L^(-1)Na2S和1mol·L^(-1)NaOH为电解质,阴极:析氢反应(hydrogen evolution reaction,HER)用1 mol·L^(-1)Na OH为电解质)进行双电极硫氧化辅助电解水制氢测试,与传统的碱性电解水相比,达到100 m A·cm^(-2)电流密度所需的能耗降低了46%。本工作为低能耗电化学制氢提供了一种新思路,并证明了SOR耦合HER电解水制氢具有实际应用的可行性。
文摘电解水是可持续绿色制氢的重要方法,但阳极缓慢的析氧反应(OER)严重阻碍电解水能量转化效率的提升,利用氧化电位较低的硫离子氧化反应(SOR)替代OER与阴极析氢反应耦合可以实现能耗的大幅降低。本文通过共沉淀法成功制备了一种钴基沸石咪唑酯骨架材料(ZIF-67),通过XRD、SEM、XPS测试手段对催化材料进行了物相分析,结果表明制备的ZIF-67催化材料由许多堆积在一起的立方体纳米颗粒组成。在三电极体系中对其进行SOR催化性能测试,将ZIF-67涂敷在泡沫镍基底上作为工作电极(ZIF-67/NF),ZIF-67/NF仅需0.361 V vs.RHE的电压就可以达到50 mA·cm^(-2)的电流密度,其电催化活性远优于Co(OH)2/NF和NF。ZIF-67/NF还表现出最低的Tafel斜率(73 mA·dec^(-1))和最小的电化学阻抗,并展现出良好的稳定性。此外,对基于SOR的两电极耦合制氢体系的电化学性能进行了测试,发现所需施加电压远小于传统的全水解制氢系统,为超低能耗制氢提供一种切实可行的方案。
基金Project(51204210)supported by the National Natural Science Foundation of ChinaProject(2011AA061001)supported by the National High Technology Research and Development Program of ChinaProject(2012BAC12B04)supported by the National Science and Technology Pillar Program during the Twelfth Five-Year Plan of China
文摘In order to decrease the solubility of PbSO4 and enhance lead recovery from PbSO4 bearing wastes, CO was employed as a reductant to transform PbSO4 into Pb S. Reaction system was established and reductive thermodynamics of PbSO4 was calculated by software HSC 5.0. The effects of gas concentration, reaction temperature, time and mass of sample on reduction of PbSO4 were examined by thermogravimetry(TG) and XRD. Roasting tests further verify the conclusions of thermodynamic and TG analyses. The results show that increasing temperature in the reasonable range and CO content are favorable for the formation of Pb S. The reduction process is controlled by chemical reaction and calculation value of the activation energy is 47.88 k J/mol.
基金Project(51364009) supported by the National Natural Science Foundation of ChinaProject(JSU071302) supported by the Construct Program of the Key Discipline in Hunan Province,ChinaProject(2015JJ2115) supported by the Natural Science Foundation of Hunan Province,China
文摘The leaching kinetics of molybdenum from Ni-Mo ore in sulfuric acid solution with sodium peroxodisulfate was studied.The effects including leaching temperature, reaction time, particle size, stirring speed, and concentrations of sulfuric acid and sodium peroxodisulfate were investigated. The leaching process of molybdenum from Ni-Mo ore is controlled by the chemical reaction through the solid layer across the unreacted shrinking core. The apparent activation energy of the leaching of molybdenum is calculated to be 41.0 k J/mol and the leaching kinetics equation of molybdenum from Ni-Mo ore is expressed as1-(1-a)1/3=3405.7exp[-41030.0/(RT)]t.
基金Project(2010CB630903) supported by the National Basic Research Program of ChinaProject(50621063) supported by the National Natural Science Foundation of China
文摘Electrochimcal behaviors of rusticyanin （Rus.） isolated from Acidithiobacillus ferrooxidans were investigated through Rus.-ZnS-QDs/L-Cys/Au electrode. The cyclic voltammetric results indicate that rusticyanin immobilized on the surface of Rus.-ZnS-QDs/L-Cys/Au electrode can undergo a direct quasi-reversible electrochemical reaction. The immobilized rusticyanin is not denatured and still retains its activity in the temperature range of 19-43 ℃. The reduction ability of the protein increases and its oxidation ability becomes weak with the increase of pH from 6.0 to 7.8. Fe^2＋ ions in the solution can promote the electron transfer kinetics of the immobilized rusticyanin and make its peak potentials （φp） markedly move negatively.
