Two-dimensional transition metal carbides(MXenes) have been demonstrated to be promising supports for single-atom catalysts(SACs) to enable efficient oxygen evolution reaction(OER).However,the rational design of MXene...Two-dimensional transition metal carbides(MXenes) have been demonstrated to be promising supports for single-atom catalysts(SACs) to enable efficient oxygen evolution reaction(OER).However,the rational design of MXene-based SACs depends on an experimental trial-and-error approach.A theoretical guidance principle is highly expected for the efficient evaluation of MXene-based SACs.Herein,highthroughput screening was performed through first-principles calculations and machine learning techniques.Ti_(3)C_(2)(OH)_(x),V_(3)C_(2)(OH)_(x),Zr_(3)C_(2)(OH)_(x),Nb_(3)C_(2)(OH)_(x),Hf_(3)C_(2)(OH)_(x),Ta_(3)C_(2)(OH)_(x),and W_(3)C_(2)(OH)_(x) were screened out based on their excellent stability.Zn,Pd,Ag,Cd,Au,and Hg were proposed to be promising single atoms anchored in MXenes based on cohesive energy analysis.Hf_(3)C_(2)(OH)_(x) with a Pd single atom delivers a theoretical overpotential of 81 mV.Both moderate electron-deficient state and high covalency of metal-carbon bonds were critical features for the high OER reactivity.This principle is expected to be a promising approach to the rational design of OER catalysts for metal-air batteries,fuel cells,and other OER-based energy storage devices.展开更多
Diamond, cubic boron nitride(c-BN), silicon(Si), and germanium(Ge), as examples of typical strong covalent materials, have been extensively investigated in recent decades, owing to their fundamental importance in mate...Diamond, cubic boron nitride(c-BN), silicon(Si), and germanium(Ge), as examples of typical strong covalent materials, have been extensively investigated in recent decades, owing to their fundamental importance in material science and industry. However, an in-depth analysis of the character of these materials' mechanical behaviors under harsh service environments, such as high pressure, has yet to be conducted. Based on several mechanical criteria, the effect of pressure on the mechanical properties of these materials is comprehensively investigated.It is demonstrated that, with respect to their intrinsic brittleness/ductile nature, all these materials exhibit ubiquitous pressure-enhanced ductility. By analyzing the strength variation under uniform deformation, together with the corresponding electronic structures, we reveal for the first time that the pressure-induced mechanical softening/weakening exhibits distinct characteristics between diamond and c-BN, owing to the differences in their abnormal charge-depletion evolution under applied strain, whereas a monotonous weakening phenomenon is observed in Si and Ge. Further investigation into dislocation-mediated plastic resistance indicates that the pressure-induced shuffle-set plane softening in diamond(c-BN), and weakening in Si(Ge), can be attributed to the reduction of antibonding states below the Fermi level, and an enhanced metallization, corresponding to the weakening of the bonds around the slipped plane with increasing pressure, respectively. These findings not only reveal the physical mechanism of pressure-induced softening/weakening in covalent materials, but also highlights the necessity of exploring strain-tunable electronic structures to emphasize the mechanical response in such covalent materials.展开更多
Lithium metal batteries(LMBs)of an ultrahigh theoretical energy density have attracted lots of attentions for a wide range of practical applications.However,there are still numerous challenges in LMBs system,such as p...Lithium metal batteries(LMBs)of an ultrahigh theoretical energy density have attracted lots of attentions for a wide range of practical applications.However,there are still numerous challenges in LMBs system,such as poor cycling performance,complicated interfacial reactions,low Coulombic efficiency,and uncontrollable lithium dendrites.Understanding Li^+ions’nucleation mechanism is essential to tackle the uncontrolled growth of lithium dendrites.However,the nucleation behavior of Li+ions is interfered by the structural complexities of existing substrates during the reduplicative plating/stripping process and the rational mechanism of uniform nucleation of Li^+ions has not been clearly understood from the theoretical point of view.In our work,first-principles theoretical calculations are carried out to investigate the Li^+ions nucleation performance on metal-doped Cu surfaces(MDCSs)and the key descriptors that determines the properties of various MDCSs are systematically summarized.It is found that the introduction of heterogeneous doping Ag and Zn atoms will induce a gradient adsorption energy on MDCSs,and such gradient deposition sites can reduce the diffusion barriers and accelerate the diffusion rates of Li+ions dynamically.By maneuvering the Li+ions nucleation on MDCSs,a dendrite-free lithium metal anode can be achieved without the use of porous matrixes and complex synthesis process,which can be attributed to suppress the uncontrollable lithium dendrites for realizing the high-efficiency LMBs.展开更多
As a new type of green energy, lithium-ion battery(LIB) has been widely used in various electric portable devices because of its high-voltage, large specific capacity, long cycle life and environmental friendliness [1...As a new type of green energy, lithium-ion battery(LIB) has been widely used in various electric portable devices because of its high-voltage, large specific capacity, long cycle life and environmental friendliness [1,2]. However, today’s anode materials of commercial LIBs cannot meet the further development requirements of smart devices and electric car due to the limitations of the electrode capacity(e.g. 372 mAh g-1 for graphite).展开更多
基金National Natural Science Foundation of China (22209094, 22209093)Research Funds of Institute of Zhejiang University-Quzhou (No. IZQ2023RCZX032)+2 种基金USTB Mat Com of Beijing Advanced Innovation Center for Materials Genome EngineeringMinistry of Education, Youth and Sports of the Czech Republic through the e-INFRA CZ (ID:90254)project Quantum materials for applications in sustainable technologies (QM4ST), funded as project No. CZ.02.01.01 /00/22_008/0004572。
文摘Two-dimensional transition metal carbides(MXenes) have been demonstrated to be promising supports for single-atom catalysts(SACs) to enable efficient oxygen evolution reaction(OER).However,the rational design of MXene-based SACs depends on an experimental trial-and-error approach.A theoretical guidance principle is highly expected for the efficient evaluation of MXene-based SACs.Herein,highthroughput screening was performed through first-principles calculations and machine learning techniques.Ti_(3)C_(2)(OH)_(x),V_(3)C_(2)(OH)_(x),Zr_(3)C_(2)(OH)_(x),Nb_(3)C_(2)(OH)_(x),Hf_(3)C_(2)(OH)_(x),Ta_(3)C_(2)(OH)_(x),and W_(3)C_(2)(OH)_(x) were screened out based on their excellent stability.Zn,Pd,Ag,Cd,Au,and Hg were proposed to be promising single atoms anchored in MXenes based on cohesive energy analysis.Hf_(3)C_(2)(OH)_(x) with a Pd single atom delivers a theoretical overpotential of 81 mV.Both moderate electron-deficient state and high covalency of metal-carbon bonds were critical features for the high OER reactivity.This principle is expected to be a promising approach to the rational design of OER catalysts for metal-air batteries,fuel cells,and other OER-based energy storage devices.
基金Supported by the National Natural Science Foundation of China (Grant No.51672015)the National Key Research and Development Program of China (Grant Nos.2016YFC1102500 and 2017YFB0702100)+3 种基金the 111 Project (Grant No.B17002)and the Fundamental Research Funds for the Central Universitiessupported by the European Regional Development Fund in the IT4Innovations National Supercomputing Center—Path to Exascale Project (Grant No.CZ.02.1.01/0.0/0.0/16 013/0001791)within the Operational Programme for Research,Development and Education,and by the Large Infrastructures for Research,Experimental Development,and Innovation Project (Grant No.e-INFRA CZ-LM2018140) by the Ministry of Education,Youth,Sport of the Czech Republic。
文摘Diamond, cubic boron nitride(c-BN), silicon(Si), and germanium(Ge), as examples of typical strong covalent materials, have been extensively investigated in recent decades, owing to their fundamental importance in material science and industry. However, an in-depth analysis of the character of these materials' mechanical behaviors under harsh service environments, such as high pressure, has yet to be conducted. Based on several mechanical criteria, the effect of pressure on the mechanical properties of these materials is comprehensively investigated.It is demonstrated that, with respect to their intrinsic brittleness/ductile nature, all these materials exhibit ubiquitous pressure-enhanced ductility. By analyzing the strength variation under uniform deformation, together with the corresponding electronic structures, we reveal for the first time that the pressure-induced mechanical softening/weakening exhibits distinct characteristics between diamond and c-BN, owing to the differences in their abnormal charge-depletion evolution under applied strain, whereas a monotonous weakening phenomenon is observed in Si and Ge. Further investigation into dislocation-mediated plastic resistance indicates that the pressure-induced shuffle-set plane softening in diamond(c-BN), and weakening in Si(Ge), can be attributed to the reduction of antibonding states below the Fermi level, and an enhanced metallization, corresponding to the weakening of the bonds around the slipped plane with increasing pressure, respectively. These findings not only reveal the physical mechanism of pressure-induced softening/weakening in covalent materials, but also highlights the necessity of exploring strain-tunable electronic structures to emphasize the mechanical response in such covalent materials.
基金supported by the National Key Research and Development Program of China(No.2017YFB0702100)the National Natural Science Foundation of China(11404017)+2 种基金the Technology Foundation for Selected Overseas Chinese Scholar,Ministry of Human Resources and Social Security of Chinasupport by the European Regional Development Fund in the IT4Innovations national supercomputing center-Path to Exascale project,No.CZ.02.1.01/0.0/0.0/16_013/0001791 within the Operational Programme Research,Development and Educationby the Ministry of Education by the Ministry of Education,Youth,and Sport of the Czech Republic and grant No.17-27790S of the Czech Science Foundations
文摘Lithium metal batteries(LMBs)of an ultrahigh theoretical energy density have attracted lots of attentions for a wide range of practical applications.However,there are still numerous challenges in LMBs system,such as poor cycling performance,complicated interfacial reactions,low Coulombic efficiency,and uncontrollable lithium dendrites.Understanding Li^+ions’nucleation mechanism is essential to tackle the uncontrolled growth of lithium dendrites.However,the nucleation behavior of Li+ions is interfered by the structural complexities of existing substrates during the reduplicative plating/stripping process and the rational mechanism of uniform nucleation of Li^+ions has not been clearly understood from the theoretical point of view.In our work,first-principles theoretical calculations are carried out to investigate the Li^+ions nucleation performance on metal-doped Cu surfaces(MDCSs)and the key descriptors that determines the properties of various MDCSs are systematically summarized.It is found that the introduction of heterogeneous doping Ag and Zn atoms will induce a gradient adsorption energy on MDCSs,and such gradient deposition sites can reduce the diffusion barriers and accelerate the diffusion rates of Li+ions dynamically.By maneuvering the Li+ions nucleation on MDCSs,a dendrite-free lithium metal anode can be achieved without the use of porous matrixes and complex synthesis process,which can be attributed to suppress the uncontrollable lithium dendrites for realizing the high-efficiency LMBs.
基金supported by National Key Research and Development Program of China (No.2017YFB0702100)the National Natural Science Foundation of China (No.11404017)+4 种基金Technology Foundation for Selected Overseas Chinese Scholar, Ministry of Human Resources and Social Security of China, Beijing Natural Science Foundation (No.20192029)supported by the European Regional Development Fund in the IT4Innovations National Supercomputing Center-Path to Exascale project, No.CZ.02.1.01/ 0.0/0.0/16_013/0001791 within the Operational Programme Research, Development and Education by the Ministry of Education, Youth, and Sport of the Czech Republicgrant No.17-27790S of the Czech Science FoundationsMobility grant No.8J18DE004 of the Ministry of Education, Youngth and Sports of the Czech RepublicSGS No.SP2019/110。
文摘As a new type of green energy, lithium-ion battery(LIB) has been widely used in various electric portable devices because of its high-voltage, large specific capacity, long cycle life and environmental friendliness [1,2]. However, today’s anode materials of commercial LIBs cannot meet the further development requirements of smart devices and electric car due to the limitations of the electrode capacity(e.g. 372 mAh g-1 for graphite).
