The metal-lightweighted electrocatalysts for water splitting are highly desired for sustainable and economic hydrogen energy deployments,but challengeable.In this work,a low-content Ni-functionalized approach triggers...The metal-lightweighted electrocatalysts for water splitting are highly desired for sustainable and economic hydrogen energy deployments,but challengeable.In this work,a low-content Ni-functionalized approach triggers the high capability of black phosphorene(BP)with hydrogen and oxygen evolution reaction(HER/OER)bifunctionality.Through a facile in situ electro-exfoliation route,the ionized Ni sites are covalently functionalized in BP nanosheets with electron redistribution and controllable metal contents.It is found that the as-fabricated Ni-BP electrocatalysts can drive the water splitting with much enhanced HER and OER activities.In 1.0 M KOH electrolyte,the optimized 1.5 wt%Nifunctionalized BP nanosheets have readily achieved low overpotentials of 136 mV for HER and 230 mV for OER at 10 mA cm^(−2).Moreover,the covalently bonding between Ni and P has also strengthened the catalytic stability of the Ni-functionalized BP electrocatalyst,stably delivering the overall water splitting for 50 h at 20 mA cm^(−2).Theoretical calculations have revealed that Ni–P covalent binding can regulate the electronic structure and optimize the reaction energy barrier to improve the catalytic activity effectively.This work confirms that Ni-functionalized BP is a suitable candidate for electrocatalytic overall water splitting,and provides effective strategies for constructing metal-lightweighted economic electrocatalysts.展开更多
In this work,a light-stimulated artificial synaptic transistor based on one-dimensional nanofibers of gallium-doped indium zinc oxides(IGZO)is demonstrated.The introduction of gallium into the nanofiber lattice can ef...In this work,a light-stimulated artificial synaptic transistor based on one-dimensional nanofibers of gallium-doped indium zinc oxides(IGZO)is demonstrated.The introduction of gallium into the nanofiber lattice can effectively alter the morphology and crystallinity,leading to a wider regulatory range of synaptic plasticity.The fabricated IGZO synaptic transistor with the optimal gallium concentration and low surface defects exhibits a superior photoresponsivity of 4300 A・W^(−1)and excellent photosensitivity,which can detect light signals as weak as 0.03 mW・cm^(−2).In particular,the paired-pulse facilitation index reaches up to 252%with over 2 h of enhanced memory retention exhibiting the long-term potentiation.Furthermore,the simulated image contrast and image recognition accuracy based on the newly designed IGZO synaptic transistors are successfully enhanced.These remarkable behaviors of light-stimulated synapses utilizing low-cost electrospun nanofibers have potential for ultraweak light applications in future artificial systems.展开更多
The strategy of element substitution is an effective way to tune the electronic structures of the active sites in catalysts, thereby leading to improvements in both the catalytic activity and stability. Herein, we des...The strategy of element substitution is an effective way to tune the electronic structures of the active sites in catalysts, thereby leading to improvements in both the catalytic activity and stability. Herein, we design and synthesize pyrite-type nickel/phosphorus co-doped CoS2 nanowires on carbon cloth （NiCoPS/CC） as efficient and durable electrodes for water electrolysis. Introduction of nickel and phosphorus produced stepwise and superb enhancement of the performance of the electrodes in the hydrogen evolution reaction due to regulation of the electronic structures of the active sites of the catalyst and accelerated charge transfer over a wide pH range （0-14）. The NiCoPS/CC electrodes also delivered a nearly undecayed catalytic current density of 10 mA.cm-2 at a low overpotential of 230 mV for oxygen evolution due to in situ formation of surficial Ni-Co oxo/hydroxide in 1.0 M KOH. Thus, the NiCoPS/CC electrodes gave rise to a catalytic current density of 10 mA·cm-2 for overall water splitting at potentials as low as 1.54 V during operation over 100 h in 1.0 M KOH with a Faradic efficiency of ~100%.展开更多
Although In2O3 nanofibers （NFs） are well-known candidates as active materials for next-generation, low-cost electronics, these NF based devices still suffer from high leakage current, insufficient on-off current rat...Although In2O3 nanofibers （NFs） are well-known candidates as active materials for next-generation, low-cost electronics, these NF based devices still suffer from high leakage current, insufficient on-off current ratios （Ion/Ioff）, and large, negative threshold voltages （VTH）, leading to poor device performance, parasitic energy consumption, and rather complicated circuit design. Here, instead of the conventional surface modification of In2O3 NFs, we present a one-step electrospinning process （i.e., without hot-press） to obtain controllable Mg-doped In2O3 NF networks to achieve high-performance enhancement-mode thin-film transistors （TFTs）. By simply adjusting the Mg doping concentration, the device performance can be manipulated precisely. For the optimal doping concentration of 2 mol%, the devices exhibit a small VTH （3.2 V）, high saturation current （1.1 × 10^-4 A）, large on/off current ratio （〉 10^8）, and respectable peak carrier mobility （2.04 cm2/（V.s））, corresponding to one of the best device performances among all 1D metal-oxide NFs based devices reported so far. When high-K HfOx thin films are employed as the gate dielectric, their electron mobility and VTH can be further improved to 5.30 cm^2/（V.s） and 0.9 V, respectivel）, which demonstrates the promising prospect of these Mg-doped In2O3 NF networks for high- performance, large-scale, and low-power electronics.展开更多
基金This work was jointly supported by the National Natural Science Foundation of China(Grant Nos.52371236 and 21872109)Natural Science Foundation of Shaanxi Province(No.2020JQ-165)China Postdoctoral Science Foundation(No.2019M663698).
文摘The metal-lightweighted electrocatalysts for water splitting are highly desired for sustainable and economic hydrogen energy deployments,but challengeable.In this work,a low-content Ni-functionalized approach triggers the high capability of black phosphorene(BP)with hydrogen and oxygen evolution reaction(HER/OER)bifunctionality.Through a facile in situ electro-exfoliation route,the ionized Ni sites are covalently functionalized in BP nanosheets with electron redistribution and controllable metal contents.It is found that the as-fabricated Ni-BP electrocatalysts can drive the water splitting with much enhanced HER and OER activities.In 1.0 M KOH electrolyte,the optimized 1.5 wt%Nifunctionalized BP nanosheets have readily achieved low overpotentials of 136 mV for HER and 230 mV for OER at 10 mA cm^(−2).Moreover,the covalently bonding between Ni and P has also strengthened the catalytic stability of the Ni-functionalized BP electrocatalyst,stably delivering the overall water splitting for 50 h at 20 mA cm^(−2).Theoretical calculations have revealed that Ni–P covalent binding can regulate the electronic structure and optimize the reaction energy barrier to improve the catalytic activity effectively.This work confirms that Ni-functionalized BP is a suitable candidate for electrocatalytic overall water splitting,and provides effective strategies for constructing metal-lightweighted economic electrocatalysts.
基金financially supported by the Natural Science Foundation of Shandong Province,China(ZR2020QF104)the Key Research and Development Program of Shandong Province,China(2019GGX102067).
基金financially supported by the Natural Science Foundation of Shandong Province,China(ZR2020QF104)the Key Research and Development Program of Shandong Province,China(2019GGX102067)。
基金the by the Natural Science Foundation of Shandong Province,China(ZR2020QF104)Key Research and Development Program of Shandong Province,China(2019GGX102067).
文摘In this work,a light-stimulated artificial synaptic transistor based on one-dimensional nanofibers of gallium-doped indium zinc oxides(IGZO)is demonstrated.The introduction of gallium into the nanofiber lattice can effectively alter the morphology and crystallinity,leading to a wider regulatory range of synaptic plasticity.The fabricated IGZO synaptic transistor with the optimal gallium concentration and low surface defects exhibits a superior photoresponsivity of 4300 A・W^(−1)and excellent photosensitivity,which can detect light signals as weak as 0.03 mW・cm^(−2).In particular,the paired-pulse facilitation index reaches up to 252%with over 2 h of enhanced memory retention exhibiting the long-term potentiation.Furthermore,the simulated image contrast and image recognition accuracy based on the newly designed IGZO synaptic transistors are successfully enhanced.These remarkable behaviors of light-stimulated synapses utilizing low-cost electrospun nanofibers have potential for ultraweak light applications in future artificial systems.
文摘The strategy of element substitution is an effective way to tune the electronic structures of the active sites in catalysts, thereby leading to improvements in both the catalytic activity and stability. Herein, we design and synthesize pyrite-type nickel/phosphorus co-doped CoS2 nanowires on carbon cloth （NiCoPS/CC） as efficient and durable electrodes for water electrolysis. Introduction of nickel and phosphorus produced stepwise and superb enhancement of the performance of the electrodes in the hydrogen evolution reaction due to regulation of the electronic structures of the active sites of the catalyst and accelerated charge transfer over a wide pH range （0-14）. The NiCoPS/CC electrodes also delivered a nearly undecayed catalytic current density of 10 mA.cm-2 at a low overpotential of 230 mV for oxygen evolution due to in situ formation of surficial Ni-Co oxo/hydroxide in 1.0 M KOH. Thus, the NiCoPS/CC electrodes gave rise to a catalytic current density of 10 mA·cm-2 for overall water splitting at potentials as low as 1.54 V during operation over 100 h in 1.0 M KOH with a Faradic efficiency of ~100%.
基金The work was financially supported by the National Natural Science Foundation of China （Nos. 51402160, 51302154, and 51672229）, the General Research Fund of the Research Grants Council of Hong Kong, China （No. CityU 11275916）, the Natural Science Foundation of Shandong Province, China （No. ZR2014EMQ011）, the Taishan Scholar Program of Shandong Province, China, the Science Technology, and Innovation Committee of Shenzhen Municipality （No. JCYJ20160229165240684）, and was supported by a grant from the Shenzhen Research Institute, City University of Hong Kong. The work was also supported by National Demonstration Center for Experimental Applied Physics Education （Qingdao University）.
文摘Although In2O3 nanofibers （NFs） are well-known candidates as active materials for next-generation, low-cost electronics, these NF based devices still suffer from high leakage current, insufficient on-off current ratios （Ion/Ioff）, and large, negative threshold voltages （VTH）, leading to poor device performance, parasitic energy consumption, and rather complicated circuit design. Here, instead of the conventional surface modification of In2O3 NFs, we present a one-step electrospinning process （i.e., without hot-press） to obtain controllable Mg-doped In2O3 NF networks to achieve high-performance enhancement-mode thin-film transistors （TFTs）. By simply adjusting the Mg doping concentration, the device performance can be manipulated precisely. For the optimal doping concentration of 2 mol%, the devices exhibit a small VTH （3.2 V）, high saturation current （1.1 × 10^-4 A）, large on/off current ratio （〉 10^8）, and respectable peak carrier mobility （2.04 cm2/（V.s））, corresponding to one of the best device performances among all 1D metal-oxide NFs based devices reported so far. When high-K HfOx thin films are employed as the gate dielectric, their electron mobility and VTH can be further improved to 5.30 cm^2/（V.s） and 0.9 V, respectivel）, which demonstrates the promising prospect of these Mg-doped In2O3 NF networks for high- performance, large-scale, and low-power electronics.
