Industrial water splitting has long been suppressed by the sluggish kinetics of the oxygen evolution reaction(OER),which requires a catalyst to be efficient.Herein,we propose a molecular-level proton acceptor strategy...Industrial water splitting has long been suppressed by the sluggish kinetics of the oxygen evolution reaction(OER),which requires a catalyst to be efficient.Herein,we propose a molecular-level proton acceptor strategy to produce an efficient OER catalyst that can boost industrial-scale water splitting.Molecular-level phosphate(-PO_(4))group is introduced to modify the surface of PrBa_(0.5)Ca_(0.5)Co_(2)O_(5)+δ(PBCC).The achieved catalyst(PO_(4)-PBCC)exhibits significantly enhanced catalytic performance in alkaline media.Based on the X-ray absorption spectroscopy results and density functional theory(DFT)calculations,the PO_(4)on the surface,which is regarded as the Lewis base,is the key factor to overcome the kinetic limitation of the proton transfer process during the OER.The use of the catalyst in a membrane electrode assembly(MEA)is further evaluated for industrial-scale water splitting,and it only needs a low voltage of 1.66 V to achieve a large current density of 1 A cm^(-2).This work provides a new molecular-level strategy to develop highly efficient OER electrocatalysts for industrial applications.展开更多
New Aurivillius phase Bi9Fe4.7Me0.3Ti3O27(Me = Fe, Co, Ni, Mn) oxides have been prepared using a citrate combustion method. X-ray diffraction on powders and high-resolution transmission electron microscopy investigati...New Aurivillius phase Bi9Fe4.7Me0.3Ti3O27(Me = Fe, Co, Ni, Mn) oxides have been prepared using a citrate combustion method. X-ray diffraction on powders and high-resolution transmission electron microscopy investigation confirmed that the Bi9Fe4.7Me0.3Ti3O27 samples are with an eight-layer structure. Both ferromagnetic and ferroelectric investigations suggested that Co or Ni substitution could enhance their multiferroic properties,while Mn substitution depressed them. Among all the samples, Bi9Fe4.7Co0.3Ti3O27 sample exhibits the largest remnant polarization of Pr*3.8 l C/cm2, and the largest remnant magnetization of Mr*0.06 lB/f.u. with a Curie temperature about 764 K, while the Bi9Fe4.7Ni0.3Ti3O27 sample has the largest spontaneous magnetization(0.26 lB/f.u.). The improved ferromagnetic properties ofboth Bi9Fe4.7Co0.3Ti3O27 and Bi9Fe4.7Ni0.3Ti3O27 can be ascribed to the spin canting of magnetic ion-based sublattices via the Dzyaloshinskii–Moriya interaction and also the magnetic ions exchanging interactions(Fe3–O–Co3or Fe3–O–Ni3).展开更多
SILICON carbide, a semiconductor with chemistry inertia, is well suited to fabricate optoelectronic device working at high temperature, high power, high frequency, and in high radiation environments. Among the hundred...SILICON carbide, a semiconductor with chemistry inertia, is well suited to fabricate optoelectronic device working at high temperature, high power, high frequency, and in high radiation environments. Among the hundreds of SiC polytypes, 4H-SiC, with a wider bandgap, a higher and much less anisotropic electron mobility than 6H-SiC, has aroused much attention .展开更多
Driven by the demands of fast-developed quantum-spintronic devices and magnetic tunneling junctions,exploring excellent magnetic insulators,which can func-tion above room temperature and have high symmetry(generally s...Driven by the demands of fast-developed quantum-spintronic devices and magnetic tunneling junctions,exploring excellent magnetic insulators,which can func-tion above room temperature and have high symmetry(generally speaking perovskite or perovskite-like struc-ture)to facilitate their integration potential with common single crystal oxide films or substrates as further devices,have drawn special attentions[1-4].Unfortunately.展开更多
Based upon the dynamic-capability view and social capital theory, this paper examines the effect of alliance orientation on firm performance. Hypotheses are tested with data collected from 195 high-tech firms in China...Based upon the dynamic-capability view and social capital theory, this paper examines the effect of alliance orientation on firm performance. Hypotheses are tested with data collected from 195 high-tech firms in China. Results show that alliance orientation has a significant and positive effect on firm performance. Moreover, market dynamism exerts a positive moderating effect on the relationship between alliance orientation and firm performance, whereas technological dynamism negatively moderates the relationship. Moreover, relational capital partially mediates the same relationship and the interaction effects of alliance orientation and market dynamism on firm performance.展开更多
基金supported by the National Natural Sci-ence Foundation of China(22272081),Jiangsu Provincial Specially Appointed Professors Foundation.
文摘Industrial water splitting has long been suppressed by the sluggish kinetics of the oxygen evolution reaction(OER),which requires a catalyst to be efficient.Herein,we propose a molecular-level proton acceptor strategy to produce an efficient OER catalyst that can boost industrial-scale water splitting.Molecular-level phosphate(-PO_(4))group is introduced to modify the surface of PrBa_(0.5)Ca_(0.5)Co_(2)O_(5)+δ(PBCC).The achieved catalyst(PO_(4)-PBCC)exhibits significantly enhanced catalytic performance in alkaline media.Based on the X-ray absorption spectroscopy results and density functional theory(DFT)calculations,the PO_(4)on the surface,which is regarded as the Lewis base,is the key factor to overcome the kinetic limitation of the proton transfer process during the OER.The use of the catalyst in a membrane electrode assembly(MEA)is further evaluated for industrial-scale water splitting,and it only needs a low voltage of 1.66 V to achieve a large current density of 1 A cm^(-2).This work provides a new molecular-level strategy to develop highly efficient OER electrocatalysts for industrial applications.
基金supported by the National Natural Science Foundation of China(U2032154)the Key Research and Development Program of Anhui(202004a05020072)+1 种基金Anhui Initiative in Quantum Information Technologies(AHY100000)Anhui Provincial Natural Science Foundation(1908085ME119)。
基金supported by the National Basic Research Program of China(2012CB922001)the National Natural Science Foundation of China(51072193)the Fundamental Research Funds for the Central Universities(WK2060140014)
文摘New Aurivillius phase Bi9Fe4.7Me0.3Ti3O27(Me = Fe, Co, Ni, Mn) oxides have been prepared using a citrate combustion method. X-ray diffraction on powders and high-resolution transmission electron microscopy investigation confirmed that the Bi9Fe4.7Me0.3Ti3O27 samples are with an eight-layer structure. Both ferromagnetic and ferroelectric investigations suggested that Co or Ni substitution could enhance their multiferroic properties,while Mn substitution depressed them. Among all the samples, Bi9Fe4.7Co0.3Ti3O27 sample exhibits the largest remnant polarization of Pr*3.8 l C/cm2, and the largest remnant magnetization of Mr*0.06 lB/f.u. with a Curie temperature about 764 K, while the Bi9Fe4.7Ni0.3Ti3O27 sample has the largest spontaneous magnetization(0.26 lB/f.u.). The improved ferromagnetic properties ofboth Bi9Fe4.7Co0.3Ti3O27 and Bi9Fe4.7Ni0.3Ti3O27 can be ascribed to the spin canting of magnetic ion-based sublattices via the Dzyaloshinskii–Moriya interaction and also the magnetic ions exchanging interactions(Fe3–O–Co3or Fe3–O–Ni3).
文摘SILICON carbide, a semiconductor with chemistry inertia, is well suited to fabricate optoelectronic device working at high temperature, high power, high frequency, and in high radiation environments. Among the hundreds of SiC polytypes, 4H-SiC, with a wider bandgap, a higher and much less anisotropic electron mobility than 6H-SiC, has aroused much attention .
基金supported by the National Key R&D Program of China(2016YFA0401004)the Chinese Universities Scientific Fund(CUSF,WK2310000055)the External Cooperation Program of BIC(Chinese Academy of Sciences,211134KYSB20130017)。
文摘Driven by the demands of fast-developed quantum-spintronic devices and magnetic tunneling junctions,exploring excellent magnetic insulators,which can func-tion above room temperature and have high symmetry(generally speaking perovskite or perovskite-like struc-ture)to facilitate their integration potential with common single crystal oxide films or substrates as further devices,have drawn special attentions[1-4].Unfortunately.
基金Acknowledgments This work is supported by the National Natural Science Foundation of China （No. 71072086）, the Humanities and Social Sciences Foundation of the Ministry of Education of China （No. 2009JJD790052）, and the Ryoichi Sasakawa Young Leaders Fellowship Fund of Sun Yat-sen University.
文摘Based upon the dynamic-capability view and social capital theory, this paper examines the effect of alliance orientation on firm performance. Hypotheses are tested with data collected from 195 high-tech firms in China. Results show that alliance orientation has a significant and positive effect on firm performance. Moreover, market dynamism exerts a positive moderating effect on the relationship between alliance orientation and firm performance, whereas technological dynamism negatively moderates the relationship. Moreover, relational capital partially mediates the same relationship and the interaction effects of alliance orientation and market dynamism on firm performance.
