Metallic Zn anodes suffer from hydrogen evolution and dendritic deposition in aqueous electrolytes,resulting in low Coulombic efficiency and poor cyclic stability for aqueous Zn-ion batteries(AZIBs).Constructing stabl...Metallic Zn anodes suffer from hydrogen evolution and dendritic deposition in aqueous electrolytes,resulting in low Coulombic efficiency and poor cyclic stability for aqueous Zn-ion batteries(AZIBs).Constructing stable solid electrolyte interphase(SEI)with strong affinity for Zn and exclusion of water corrosion of Zn metal anodes is a promising strategy to tackle these challenges.In this study,we develop a self-healing ZnO-based SEI film on the Zn electrode surface by employing an aspartame(APM)as a versatile electrolyte additive.The hydrophobic nature and strong Zn affinity of APM can facilitate the dynamic self-healing of ZnO-based SEI film during cyclic Zn plating/stripping process.Benefiting from the superior protection effect of self-healing ZnO-based SEI,the Zn║Cu cells possess an average coulombic efficiency more than 99.59%over 1,000 cycles even at a low current density of 1 m A cm^(-2)-1 m Ah cm^(-2).Furthermore,the Zn║NH_4~+-V_(2)O_5 full cells display a large specific capacity of 150 mAh g^(-1)and high cyclic stability with a capacity retention of 77.8%after 1,750 cycles.In addition,the Zn║Zn cell delivers high temperature adaptability at a wide-temperature range from-5 to 40℃ even under a high DOD of 85.2%.The enhanced capability and durability originate from the self-healing SEI formation enabled by multifunctional APM additives mediating both corrosion suppression and interfacial stabilization.This work presents an inspired and straightforward approach to promote a dendrite-free and widetemperature rechargeable AZIBs energy storage system.展开更多
Organic-inorganic nanojunctions can result in a selective scattering of charge carrier depending on their energy, which leads to a simultaneous increase in the Seebeck coefficient S and the power factor. In this work,...Organic-inorganic nanojunctions can result in a selective scattering of charge carrier depending on their energy, which leads to a simultaneous increase in the Seebeck coefficient S and the power factor. In this work, the nanojunction is successfully employed at the organic-inorganic semiconductor interface of polyparaphenylene （PPP） and Zn1-xAgxO nanoparticles through the sol-gel method. The presence of nanoinclusions PPP in Zno.gAgoa 0 matrix is found to be effective in improving the figure of merit （ZT） by the dual effects of an increase in the power factor consistent with the heterojunetion effect and a reduction in thermal conductivity. Zno.gAgo.10/0.1 wt% PPP exhibits a maximum figure of merit, i.e., ZT= 0.22.展开更多
A high voltage gradient(V_(g))of ZnO-based varistor ceramics is critical for realizing miniaturized and lightweight overvoltage protection devices.However,improving V_(g) of ZnObased varistor ceramics through conventi...A high voltage gradient(V_(g))of ZnO-based varistor ceramics is critical for realizing miniaturized and lightweight overvoltage protection devices.However,improving V_(g) of ZnObased varistor ceramics through conventional high-temperature sintering process remains a significant challenge.Here,we present a strategy to fabricate ultrahigh voltage-gradient ZnO-based varistor ceramics by combining cold sintering process/spark plasma sintering(CSP–SPS)with post-annealing process.Employing CSP–SPS,the ZnO-based varistor ceramics were initially densified at 300℃ and subsequently annealed at a low temperature of 700–900℃.CSP–SPS technique combined with a low annealing temperature enables the production of ZnO-based varistor ceramics with fine and homogeneous microstructures,while suppressing the volatilization of Bi-rich phases at grain boundaries.This approach achieves the ultrahigh V_(g) of~1832.71 V/mm,high nonlinear coefficient(α)of~106.69,and low leakage current density(J_(L))of less than 0.2μA/cm^(2).This work shows that the integration of CSP–SPS and post-annealing provides a promising way to design ZnO-based varistor ceramics with ultrahigh V_(g).展开更多
Microstructure of ZnO:Mn films with various Mn concentration was investigated with XANES and XPS. The experimental results revealed a substitution of Mn in ZnO and also excluded the existence of Mn oxides or metallic ...Microstructure of ZnO:Mn films with various Mn concentration was investigated with XANES and XPS. The experimental results revealed a substitution of Mn in ZnO and also excluded the existence of Mn oxides or metallic manganese clusters. The substitutional Mn presented a divalent state and all the ZnO:Mn films were n-type. Room temperature ferromagnetism monotonously decreases with the decrease of the electron carrier concentration. The observed ferrmagnetism should come from the carrier-mediated exchange.展开更多
Ni/ZnO nano-sponges have been successfully synthesized through optimized annealing of Ni/Zn-based organic framework (Ni/Zn-MOF). The annealed MOF provides the stable carbon structure with 3D interconnection and preven...Ni/ZnO nano-sponges have been successfully synthesized through optimized annealing of Ni/Zn-based organic framework (Ni/Zn-MOF). The annealed MOF provides the stable carbon structure with 3D interconnection and prevents structural collapse during the charging and discharging process. The annealing causes the incorporation of intrinsic Ni^(3+) in the surface of NiO nanoparticles, providing more reaction active sites. The oxygen vacancies in ZnO and heterostructure interfaces between NiO and ZnO promote the charge transformation. Based on the aforementioned advantages, the Ni/ZnO nanocomposites exhibit excellent electrocatalytic performances for supercapacitors. The specific capacitance can reach to 807 F·g^(−1) at 1 A·g^(−1) in the studied electrodes. After 5,000 cycles at 10 A·g^(−1), the cyclic stability remains excellent at 86% of the initial capacitance. Moreover, the as-prepared asymmetric supercapacitor exhibits a high energy density of 30.6 W·h·kg^(−1) at power density of 398 W·kg^(−1). This study is expected to provide new insights into exploring the potential mechanism of catalyst action.展开更多
Zn0.93Co0.07O thin films infiltrated with nitrogen and aluminum were prepared by means of magneton sputtering. The structural and magnetic properties of the films were studied systematically. The materials were single...Zn0.93Co0.07O thin films infiltrated with nitrogen and aluminum were prepared by means of magneton sputtering. The structural and magnetic properties of the films were studied systematically. The materials were single phase (wurtzite structure) with surfaces showing signs of homogeneous growth. The films were ferromagnetic at room temperature, and magnetic domains could be clearly observed on the surfaces. In the case of Al infiltration, saturated magnetization increased with Al concentration increasing; whereas in the case of N infiltration, saturated magnetization decreased with the increase in N concentration. The results show that ferromagnetic interactions in Co-doped ZnO diluted magnetic semiconductor may be transferred by electrons.展开更多
基金mainly supported by the National Natural Science Foundation of China[No.52374312]the Science and Technology Innovation Program of Hunan Province[No.2024RC3026]+2 种基金the Natural Science Foundation of Hunan Province[No.2023JJ10076]the Research Institute for Advanced Manufacturing via the project No.1-CD9C,1-CDLR,Research Project of Zhuzhou Smelting Group Co.,Ltd.[ZYGFGH2307071500015]the High Performance Computing Center of Central South University。
文摘Metallic Zn anodes suffer from hydrogen evolution and dendritic deposition in aqueous electrolytes,resulting in low Coulombic efficiency and poor cyclic stability for aqueous Zn-ion batteries(AZIBs).Constructing stable solid electrolyte interphase(SEI)with strong affinity for Zn and exclusion of water corrosion of Zn metal anodes is a promising strategy to tackle these challenges.In this study,we develop a self-healing ZnO-based SEI film on the Zn electrode surface by employing an aspartame(APM)as a versatile electrolyte additive.The hydrophobic nature and strong Zn affinity of APM can facilitate the dynamic self-healing of ZnO-based SEI film during cyclic Zn plating/stripping process.Benefiting from the superior protection effect of self-healing ZnO-based SEI,the Zn║Cu cells possess an average coulombic efficiency more than 99.59%over 1,000 cycles even at a low current density of 1 m A cm^(-2)-1 m Ah cm^(-2).Furthermore,the Zn║NH_4~+-V_(2)O_5 full cells display a large specific capacity of 150 mAh g^(-1)and high cyclic stability with a capacity retention of 77.8%after 1,750 cycles.In addition,the Zn║Zn cell delivers high temperature adaptability at a wide-temperature range from-5 to 40℃ even under a high DOD of 85.2%.The enhanced capability and durability originate from the self-healing SEI formation enabled by multifunctional APM additives mediating both corrosion suppression and interfacial stabilization.This work presents an inspired and straightforward approach to promote a dendrite-free and widetemperature rechargeable AZIBs energy storage system.
基金Supported by the National Natural Science Foundation of China under Grant Nos 51476095 and 51206103the Innovation Program of Shanghai Municipal Education Commission under Grant No 13YZ128the Program for Professor of Special Appointment(Eastern Scholar) at Shanghai Institutions of Higher Learning
文摘Organic-inorganic nanojunctions can result in a selective scattering of charge carrier depending on their energy, which leads to a simultaneous increase in the Seebeck coefficient S and the power factor. In this work, the nanojunction is successfully employed at the organic-inorganic semiconductor interface of polyparaphenylene （PPP） and Zn1-xAgxO nanoparticles through the sol-gel method. The presence of nanoinclusions PPP in Zno.gAgoa 0 matrix is found to be effective in improving the figure of merit （ZT） by the dual effects of an increase in the power factor consistent with the heterojunetion effect and a reduction in thermal conductivity. Zno.gAgo.10/0.1 wt% PPP exhibits a maximum figure of merit, i.e., ZT= 0.22.
基金supported by the Joint Funds of the National Natural Science Foundation of China(No.U23B20115)the Fok Ying-Tong Education Foundation,China(No.171050)。
文摘A high voltage gradient(V_(g))of ZnO-based varistor ceramics is critical for realizing miniaturized and lightweight overvoltage protection devices.However,improving V_(g) of ZnObased varistor ceramics through conventional high-temperature sintering process remains a significant challenge.Here,we present a strategy to fabricate ultrahigh voltage-gradient ZnO-based varistor ceramics by combining cold sintering process/spark plasma sintering(CSP–SPS)with post-annealing process.Employing CSP–SPS,the ZnO-based varistor ceramics were initially densified at 300℃ and subsequently annealed at a low temperature of 700–900℃.CSP–SPS technique combined with a low annealing temperature enables the production of ZnO-based varistor ceramics with fine and homogeneous microstructures,while suppressing the volatilization of Bi-rich phases at grain boundaries.This approach achieves the ultrahigh V_(g) of~1832.71 V/mm,high nonlinear coefficient(α)of~106.69,and low leakage current density(J_(L))of less than 0.2μA/cm^(2).This work shows that the integration of CSP–SPS and post-annealing provides a promising way to design ZnO-based varistor ceramics with ultrahigh V_(g).
文摘Microstructure of ZnO:Mn films with various Mn concentration was investigated with XANES and XPS. The experimental results revealed a substitution of Mn in ZnO and also excluded the existence of Mn oxides or metallic manganese clusters. The substitutional Mn presented a divalent state and all the ZnO:Mn films were n-type. Room temperature ferromagnetism monotonously decreases with the decrease of the electron carrier concentration. The observed ferrmagnetism should come from the carrier-mediated exchange.
基金This work was supported by the National Natural Science Foundation of China(Nos.11975043 and 11605007).
文摘Ni/ZnO nano-sponges have been successfully synthesized through optimized annealing of Ni/Zn-based organic framework (Ni/Zn-MOF). The annealed MOF provides the stable carbon structure with 3D interconnection and prevents structural collapse during the charging and discharging process. The annealing causes the incorporation of intrinsic Ni^(3+) in the surface of NiO nanoparticles, providing more reaction active sites. The oxygen vacancies in ZnO and heterostructure interfaces between NiO and ZnO promote the charge transformation. Based on the aforementioned advantages, the Ni/ZnO nanocomposites exhibit excellent electrocatalytic performances for supercapacitors. The specific capacitance can reach to 807 F·g^(−1) at 1 A·g^(−1) in the studied electrodes. After 5,000 cycles at 10 A·g^(−1), the cyclic stability remains excellent at 86% of the initial capacitance. Moreover, the as-prepared asymmetric supercapacitor exhibits a high energy density of 30.6 W·h·kg^(−1) at power density of 398 W·kg^(−1). This study is expected to provide new insights into exploring the potential mechanism of catalyst action.
基金Supported by the National Natural Science Foundation of China (Grant No.10674059)the Major Project of National Basic Research Program of China (Grant No.2005CB623605)
文摘Zn0.93Co0.07O thin films infiltrated with nitrogen and aluminum were prepared by means of magneton sputtering. The structural and magnetic properties of the films were studied systematically. The materials were single phase (wurtzite structure) with surfaces showing signs of homogeneous growth. The films were ferromagnetic at room temperature, and magnetic domains could be clearly observed on the surfaces. In the case of Al infiltration, saturated magnetization increased with Al concentration increasing; whereas in the case of N infiltration, saturated magnetization decreased with the increase in N concentration. The results show that ferromagnetic interactions in Co-doped ZnO diluted magnetic semiconductor may be transferred by electrons.
