The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation...The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation supported by experimental evidence remains lacking. This work investigates the effects of fluorine incorporation and electrothermal annealing(ETA) on the current transport process at Ni/β-Ga_(2)O_(3) Schottky contacts. X-ray photoelectron spectroscopy and first-principles calculations confirm the presence of fluorine substitutions for oxygen and oxygen vacancies and their lowering effect on the Schottky barrier heights. Additionally, accurate electrothermal hybrid TCAD simulations validates the extremely short-duration high temperatures(683 K) induced by ETA, which facilitates lattice rearrangement and reduces interface trap states. The interface trap states are quantitatively resolved through frequency-dependent conductance technique, showing the trap density(DT)reduction from(0.88-2.48) × 10^(11) cm^(-2)·eV^(-1) to(0.46-2.09) × 10^(11) cm^(-2)·eV^(-1). This investigation offers critical insights into the β-Ga_(2)O_(3) contacts with the collaborative treatment and solids the promotion of high-performance β-Ga_(2)O_(3) power devices.展开更多
The electrocatalytic reduction of carbon dioxide(CO_(2)RR)to valuable products presents a promising solution for addressing global warming and enhancing renewable energy storage.Herein,we construct a novel Ni_(3)ZnC_(...The electrocatalytic reduction of carbon dioxide(CO_(2)RR)to valuable products presents a promising solution for addressing global warming and enhancing renewable energy storage.Herein,we construct a novel Ni_(3)ZnC_(0.7)/Ni heterostructure electrocatalyst,using an electrospinning strategy to prepare metal particles uniformly loaded on nitrogen-doped carbon nanofibers(CNFs).The incorporation of zinc(Zn)into nickel(Ni)catalysts optimizes the adsorption of CO_(2)intermediates,balancing the strong binding affinity of Ni with the comparatively weaker affinity of Zn,which mitigates over-activation.The electron transfer within the Ni_(3)ZnC_(0.7)/Ni@CNFs system facilitates rapid electron transfer to CO_(2),resulting in great performance with a faradaic efficiency for CO(FECO)of nearly 90%at−0.86 V versus the reversible hydrogen electrode(RHE)and a current density of 17.51 mA cm^(−2)at−1.16 V versus RHE in an H-cell.Furthermore,the catalyst exhibits remarkable stability,maintaining its crystal structure and morphology after 50 h of electrolysis.Moreover,the Ni_(3)ZnC_(0.7)/Ni@CNFs is used in the membrane electrode assembly reactor(MEA),which can achieve a FECO of 91.7%at a cell voltage of−3 V and a current density of 200 mA cm−2 at−3.9 V,demonstrating its potential for practical applications in CO_(2)reduction.展开更多
The layered Li[Ni1/3Mn1/3Co1/3]O2 was separately synthesized by pretreatment process of ball mill method and solution phase route, using [Ni1/3Co1/3Mn1/3]3O4 and lithium hydroxide as raw materials. The physical and el...The layered Li[Ni1/3Mn1/3Co1/3]O2 was separately synthesized by pretreatment process of ball mill method and solution phase route, using [Ni1/3Co1/3Mn1/3]3O4 and lithium hydroxide as raw materials. The physical and electrochemical behaviors of Li[Ni1/3Mn1/3Co1/3]O2 were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, field emission scanning electron microscopy （FESEM） and electrochemical charge/discharge cycling tests. The results show that the difference in pretreatment process results in the difference in compound Li[Ni1/3Co1/3Mn1/3]O2 structure, morphology and the electrochemical characteristics. The Li[Ni1/3Mn1/3Co1/3]O2 prepared by solution phase route maintains the uniform spherical morphology of the [Ni1/3Co1/3Mn1/3]3O4, and it exhibits a higher capacity retention and better rate capability than that prepared by ball mill method. The initial discharge capacity of this sample reaches 178 mA-h/g and the capacity retention after 50 cycles is 98.7% at a current density of 20 mA/g. Moreover, it delivers high discharge capacity of 135 mA-h/g at a current density of 1 000 mA/g.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 62174019, 52302046, L2424216)the Guangdong Basic and Applied Basic Research Foundation (Grant No. 2024A1515012139)+2 种基金the Major Program (JD) of Hubei Province (Grant No. 2023BAA009)the Knowledge Innovation Program of Wuhan-Shuguang Project (Grant No. 2023010201020262)the Basic Research Program of Jiangsu (Grant No. BK20230268)。
文摘The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation supported by experimental evidence remains lacking. This work investigates the effects of fluorine incorporation and electrothermal annealing(ETA) on the current transport process at Ni/β-Ga_(2)O_(3) Schottky contacts. X-ray photoelectron spectroscopy and first-principles calculations confirm the presence of fluorine substitutions for oxygen and oxygen vacancies and their lowering effect on the Schottky barrier heights. Additionally, accurate electrothermal hybrid TCAD simulations validates the extremely short-duration high temperatures(683 K) induced by ETA, which facilitates lattice rearrangement and reduces interface trap states. The interface trap states are quantitatively resolved through frequency-dependent conductance technique, showing the trap density(DT)reduction from(0.88-2.48) × 10^(11) cm^(-2)·eV^(-1) to(0.46-2.09) × 10^(11) cm^(-2)·eV^(-1). This investigation offers critical insights into the β-Ga_(2)O_(3) contacts with the collaborative treatment and solids the promotion of high-performance β-Ga_(2)O_(3) power devices.
基金financial support from the Natural Science Foundation of Yancheng(YCBK2024004)the Basic Research Program of Jiangsu(BK20251089)the“Scientific and Technical Innovation Action Plan”Basic Research Field of Shanghai Science and Technology Committee(19JC1410500).
文摘The electrocatalytic reduction of carbon dioxide(CO_(2)RR)to valuable products presents a promising solution for addressing global warming and enhancing renewable energy storage.Herein,we construct a novel Ni_(3)ZnC_(0.7)/Ni heterostructure electrocatalyst,using an electrospinning strategy to prepare metal particles uniformly loaded on nitrogen-doped carbon nanofibers(CNFs).The incorporation of zinc(Zn)into nickel(Ni)catalysts optimizes the adsorption of CO_(2)intermediates,balancing the strong binding affinity of Ni with the comparatively weaker affinity of Zn,which mitigates over-activation.The electron transfer within the Ni_(3)ZnC_(0.7)/Ni@CNFs system facilitates rapid electron transfer to CO_(2),resulting in great performance with a faradaic efficiency for CO(FECO)of nearly 90%at−0.86 V versus the reversible hydrogen electrode(RHE)and a current density of 17.51 mA cm^(−2)at−1.16 V versus RHE in an H-cell.Furthermore,the catalyst exhibits remarkable stability,maintaining its crystal structure and morphology after 50 h of electrolysis.Moreover,the Ni_(3)ZnC_(0.7)/Ni@CNFs is used in the membrane electrode assembly reactor(MEA),which can achieve a FECO of 91.7%at a cell voltage of−3 V and a current density of 200 mA cm−2 at−3.9 V,demonstrating its potential for practical applications in CO_(2)reduction.
基金supported by the National Natural Science Foundation of China(21703194)the Natural Science Foundation of Jiangsu Province(BK20171168,BK20171169)+2 种基金Natural Science Foundation of Jiangsu Higher Education Institutions of China(17KJB530010,17KJB150038 and18KJA430015)Key Research Project of Social Development of Xuzhou(KC17154)Research Project of Xuzhou University of Technology(XKY2017217)
基金Project(20871101)supported by the National Natural Science Foundation of ChinaProject(2009WK2007)supported by Key Project of Science and Technology Department of Hunan Province,ChinaProject(CX2009B133)supported by Colleges and Universities in Hunan Province Plans to Graduate Research and Innovation,China
文摘The layered Li[Ni1/3Mn1/3Co1/3]O2 was separately synthesized by pretreatment process of ball mill method and solution phase route, using [Ni1/3Co1/3Mn1/3]3O4 and lithium hydroxide as raw materials. The physical and electrochemical behaviors of Li[Ni1/3Mn1/3Co1/3]O2 were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, field emission scanning electron microscopy （FESEM） and electrochemical charge/discharge cycling tests. The results show that the difference in pretreatment process results in the difference in compound Li[Ni1/3Co1/3Mn1/3]O2 structure, morphology and the electrochemical characteristics. The Li[Ni1/3Mn1/3Co1/3]O2 prepared by solution phase route maintains the uniform spherical morphology of the [Ni1/3Co1/3Mn1/3]3O4, and it exhibits a higher capacity retention and better rate capability than that prepared by ball mill method. The initial discharge capacity of this sample reaches 178 mA-h/g and the capacity retention after 50 cycles is 98.7% at a current density of 20 mA/g. Moreover, it delivers high discharge capacity of 135 mA-h/g at a current density of 1 000 mA/g.
