Inorganic metal oxide electrochromic materials have good application prospects for energy-saving windows in buildings and smart display applications.Therefore,the development of electrochromic films with good cycling ...Inorganic metal oxide electrochromic materials have good application prospects for energy-saving windows in buildings and smart display applications.Therefore,the development of electrochromic films with good cycling stabilities,fast color-change response times,and high coloring efficiencies has attracted considerable attention.In this study,nanoflake Li-doped NiO electrochromic films were prepared using a hydrothermal method,and the films exhibited superior electrochromic performances in the LiOH electrolyte.Li^(+)ions doping increased the ion transmission rates of the NiO films,and effectively promoted the transportation of ions from the electrolyte into NiO films.Meanwhile,the nanoflake microstructure caused the NiO films to have larger specific surface areas,providing more active sites for electrochemical reactions.It was determined that the NiO-Li20%film exhibited an ultra-fast response in the LiOH electrolyte(coloring and bleaching times reached 3 and 1.5 s,respectively).Additionally,the coloration efficiency was 62.1 cm^(2)C^(−1),and good cycling stability was maintained beyond 1500 cycles.Finally,the simulation calculation results showed that Li doping weakened the adsorption strengths of the NiO films to OH^(−),which reduced the generation and decomposition of NiOOH and helped to improve the cycling stabilities of the films.Therefore,the research presented in this article provides a strategy for designing electrochromic materials in the future.展开更多
We research the adsorption geometries graphene （Li-GR） before and after CO and electronic structures of pristine graphene （p-GR） and Li-doped adsorption by first-principles. The adsorption energies Ead of CO on p-...We research the adsorption geometries graphene （Li-GR） before and after CO and electronic structures of pristine graphene （p-GR） and Li-doped adsorption by first-principles. The adsorption energies Ead of CO on p-GR and Li-GR are calculated. The results demonstrate that Ead of CO on Li-GR is from -3.3 eV to -3.5 eV, meanwhile Q is up to 0.13e, which indicate that strong electrostatic attractions occur between CO and Li-GR, while CO is physically adsorbed on p-GR. The obvious accumulated charge in electron density difference and increasing carrier density suggest that the conductivity of Li-GR is improved considerably after CO adsorp- tion. An adsorption mechanism is also proposed. Our results provide a path to achieving CO sensors with high performance.展开更多
In this letter the study of Li-doped zinc oxide by electron paramagnetic resonance method is described.A signal observed at g_=2.013,g_=1.955 on the degassed sample at 923K was designated to F_s^+ centers(surface oxyg...In this letter the study of Li-doped zinc oxide by electron paramagnetic resonance method is described.A signal observed at g_=2.013,g_=1.955 on the degassed sample at 923K was designated to F_s^+ centers(surface oxygen ion vacancies with a single trapped electron).When the sample was quenched from 1003K into liquid oxygen at 77K under 24 KPa O_2,[Li^+O^-] ion pairs valued at g_=2.026 and g=2.003 with superhyperfine constant a=2.0G,which resulted from ~7Li nucleus,formed at Li^+-substitutional site in ZnO lattice.A probable mechanism of [Li^+O^-]ion pair formation was proposed.展开更多
P2-type layered oxides have been considered as promising cathode materials for Na-ion batteries,but the capac-ity decay resulting from the Na+/vacancy ordering and phase transformation limits their future large-scale ...P2-type layered oxides have been considered as promising cathode materials for Na-ion batteries,but the capac-ity decay resulting from the Na+/vacancy ordering and phase transformation limits their future large-scale applica-tions.Herein,the impact of Li-doping in different layers on the structure and electrochemical performance of P2-type Na_(0.7)Ni_(0.35)Mn_(0.65)O_(2) is investigated.It can be found that Li ions successfully enter both the Na and transition metal layers.The strategy of Li-doping can improve the cycling stability and rate capability of P2-type layered oxides,which promotes the development of high-performance Na-ion batteries.展开更多
Antimony sulfide(Sb_(2)S_(3))thin film have a suitable band gap(1.73 eV)and high absorption coefficient,indicating potential prospects in indoor photovoltaics.The open-circuit voltage(VOC)attenuation under indoor weak...Antimony sulfide(Sb_(2)S_(3))thin film have a suitable band gap(1.73 eV)and high absorption coefficient,indicating potential prospects in indoor photovoltaics.The open-circuit voltage(VOC)attenuation under indoor weak light limits the performance and application,which is affected by the heterojunction interface quality.Hence,we propose a hole transport layer free Sb_(2)S_(3) indoor photovoltaic cell using Lidoped TiO_(2) as the electron transport layer to overcome weaklight VOC loss.The Li-doped TiO_(2) films prepared by spray pyrolysis LiCl additive precursor reveal higher surface potentials,enhancing electron collections.The doped interface also promoted subsequent grain growth of Sb_(2)S_(3) thin film.The champion device,configured as FTO/TiO_(2):Li/Sb_(2)S_(3)/Au,achieves an efficiency of 6.12%with an optimal Li doping ratio of 8%in the TiO_(2) layer.The Li introduction at the junction interface suppresses the photocarrier recombinations under indoor light,thus improving device performance.The indoor power conversion efficiency of the Li-TiO_(2) based Sb_(2)S_(3) device reaches 12.7%under the irradiation of 1000-lux LED,showing 48%improvement compared with the undoped device.The Li-doped TiO_(2)/Sb_(2)S_(3) photovoltaic device demonstrates significant advantages,particularly in cold and monochromatic light conditions,opening new prospects for indoor application.展开更多
基金supported by the Key Science and Technology Innovation Team of Shaanxi Province(No.2014KCT-03)Special Support Program for High-level Talents of Shaanxi Province(No.2020-44)China Postdoctoral Science Foundation(No.2019M663990).
文摘Inorganic metal oxide electrochromic materials have good application prospects for energy-saving windows in buildings and smart display applications.Therefore,the development of electrochromic films with good cycling stabilities,fast color-change response times,and high coloring efficiencies has attracted considerable attention.In this study,nanoflake Li-doped NiO electrochromic films were prepared using a hydrothermal method,and the films exhibited superior electrochromic performances in the LiOH electrolyte.Li^(+)ions doping increased the ion transmission rates of the NiO films,and effectively promoted the transportation of ions from the electrolyte into NiO films.Meanwhile,the nanoflake microstructure caused the NiO films to have larger specific surface areas,providing more active sites for electrochemical reactions.It was determined that the NiO-Li20%film exhibited an ultra-fast response in the LiOH electrolyte(coloring and bleaching times reached 3 and 1.5 s,respectively).Additionally,the coloration efficiency was 62.1 cm^(2)C^(−1),and good cycling stability was maintained beyond 1500 cycles.Finally,the simulation calculation results showed that Li doping weakened the adsorption strengths of the NiO films to OH^(−),which reduced the generation and decomposition of NiOOH and helped to improve the cycling stabilities of the films.Therefore,the research presented in this article provides a strategy for designing electrochromic materials in the future.
基金Supported by the National Natural Science Foundation of China under Grant Nos 51372282,51072024 and 51132002the National College Students’Innovative and Entrepreneurial Training Program of Beijing Institute of Technology under Grant No201410007050
文摘We research the adsorption geometries graphene （Li-GR） before and after CO and electronic structures of pristine graphene （p-GR） and Li-doped adsorption by first-principles. The adsorption energies Ead of CO on p-GR and Li-GR are calculated. The results demonstrate that Ead of CO on Li-GR is from -3.3 eV to -3.5 eV, meanwhile Q is up to 0.13e, which indicate that strong electrostatic attractions occur between CO and Li-GR, while CO is physically adsorbed on p-GR. The obvious accumulated charge in electron density difference and increasing carrier density suggest that the conductivity of Li-GR is improved considerably after CO adsorp- tion. An adsorption mechanism is also proposed. Our results provide a path to achieving CO sensors with high performance.
基金Supported by Chinese National Scientific Foundation
文摘In this letter the study of Li-doped zinc oxide by electron paramagnetic resonance method is described.A signal observed at g_=2.013,g_=1.955 on the degassed sample at 923K was designated to F_s^+ centers(surface oxygen ion vacancies with a single trapped electron).When the sample was quenched from 1003K into liquid oxygen at 77K under 24 KPa O_2,[Li^+O^-] ion pairs valued at g_=2.026 and g=2.003 with superhyperfine constant a=2.0G,which resulted from ~7Li nucleus,formed at Li^+-substitutional site in ZnO lattice.A probable mechanism of [Li^+O^-]ion pair formation was proposed.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12105372 and 51991344)President's Foundation of China Institute of Atomic Energy(Grant No.16YZ202212000201)Chinese Academy of Sciences(Grant No.XDB33000000).
文摘P2-type layered oxides have been considered as promising cathode materials for Na-ion batteries,but the capac-ity decay resulting from the Na+/vacancy ordering and phase transformation limits their future large-scale applica-tions.Herein,the impact of Li-doping in different layers on the structure and electrochemical performance of P2-type Na_(0.7)Ni_(0.35)Mn_(0.65)O_(2) is investigated.It can be found that Li ions successfully enter both the Na and transition metal layers.The strategy of Li-doping can improve the cycling stability and rate capability of P2-type layered oxides,which promotes the development of high-performance Na-ion batteries.
基金supported by the National Natural Science Foundation of China(Nos.52372183,62474043 and 52002073)Fujian Provincial Natural Science Foundation of China(No.2024J09015)+2 种基金Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZZ124)Foundation of Fujian Provincial Department of Industry and Information Technology of China(No.82318075)Fuzhou University(No.XRC-24072).
文摘Antimony sulfide(Sb_(2)S_(3))thin film have a suitable band gap(1.73 eV)and high absorption coefficient,indicating potential prospects in indoor photovoltaics.The open-circuit voltage(VOC)attenuation under indoor weak light limits the performance and application,which is affected by the heterojunction interface quality.Hence,we propose a hole transport layer free Sb_(2)S_(3) indoor photovoltaic cell using Lidoped TiO_(2) as the electron transport layer to overcome weaklight VOC loss.The Li-doped TiO_(2) films prepared by spray pyrolysis LiCl additive precursor reveal higher surface potentials,enhancing electron collections.The doped interface also promoted subsequent grain growth of Sb_(2)S_(3) thin film.The champion device,configured as FTO/TiO_(2):Li/Sb_(2)S_(3)/Au,achieves an efficiency of 6.12%with an optimal Li doping ratio of 8%in the TiO_(2) layer.The Li introduction at the junction interface suppresses the photocarrier recombinations under indoor light,thus improving device performance.The indoor power conversion efficiency of the Li-TiO_(2) based Sb_(2)S_(3) device reaches 12.7%under the irradiation of 1000-lux LED,showing 48%improvement compared with the undoped device.The Li-doped TiO_(2)/Sb_(2)S_(3) photovoltaic device demonstrates significant advantages,particularly in cold and monochromatic light conditions,opening new prospects for indoor application.
