以丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为起始原料,采用氧化还原/偶氮类复合引发体系,在金属卤化物灯的辅助下,制备了性能优良的阳离子聚丙烯酰胺(CPAM)。最佳反应条件下所得产物的特性粘数可达13.87 d L·g^(-1),溶解时间...以丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为起始原料,采用氧化还原/偶氮类复合引发体系,在金属卤化物灯的辅助下,制备了性能优良的阳离子聚丙烯酰胺(CPAM)。最佳反应条件下所得产物的特性粘数可达13.87 d L·g^(-1),溶解时间38 min。利用红外光谱(FTIR)、核磁共振氢谱(~1H-NMR)对产物的结构进行了详细表征。进一步研究了CPAM用量和特性粘数对其助留助滤性能的影响,并与国外同类产品进行了助留助滤性能比较。展开更多
Transition metal sulfide-based hydrogen evolution electrocatalysts still lag in catalytic activity due to the zero-deviated free energy of*H adsorption.Plasmonic metals bridge the gap between light utilization and pla...Transition metal sulfide-based hydrogen evolution electrocatalysts still lag in catalytic activity due to the zero-deviated free energy of*H adsorption.Plasmonic metals bridge the gap between light utilization and plasmon-mediated redox reactions for substantially enhanced electrocatalytic activity.In this work,a strategic broadband light utilization heterostructure,composed of two distinct Ag nanostructures(discontinuous Ag nanorods and monodispersed nanoparticles),is achieved through in situ sulfurization and metal leaching.The heterostructure benefits the electrocatalytic hydrogen evolution reactivity thanks to the localized surface plasmon resonance induced hot electrons injection and inter-gap electric fields revealed by the finite-difference time-domain simulation.Experimentally,the prudent heterostructured catalyst exhibits a significantly improved overpotential(at 10 mA cm−2)from 151 to 95 mV along with a Tafel slope from 74 to 45 mV dec−1 toward hydrogen evolution.Significantly,this instructional study sheds light on the design of hybrid photo-assisted electrocatalysts with cooperative effect of solar energy toward sustainable electrocatalysis.展开更多
The Z-scheme heterostructure for photocatalyst can effectively prolong the lifetime of photogenerated carriers and retain a higher conduction/valence band position,promoting the synergistic coupling of photocatalysis ...The Z-scheme heterostructure for photocatalyst can effectively prolong the lifetime of photogenerated carriers and retain a higher conduction/valence band position,promoting the synergistic coupling of photocatalysis and peroxymonosulfate(PMS) activation.In order to fully utilize the luminous energy and realize the efficient activation of PMS,this work achieved successful construction of NiCo_(2)O_(4)/BiOCl/Bi_(24)O_(31)Br_(10) ternary Z-scheme heterojunction by simultaneously synthesizing BiOCl and NiCo_(2)O_(4) with NiCl_(2) and CoCl_(2) as the precursors.The intercalated BiOCl could serve as a carrier migration ladder to further achieve the spatial separation of electron-hole pairs,so that the oxidation and reduction processes separately occurred in different regions.Compared with the reported catalysts,the as-prepared composites exhibited the enhanced removal efficiency for tetracycline hydrochloride(TCH) in the visible light/PMS system,with a degradation efficiency of 85.30%in 2 min,and possessed good stability.Z-scheme heterojunction was shown to be beneficial for maximizing the superiority of photo-assisted Fenton-like reaction system.The experimental and characterization results confirmed that both non-radicals(^(1)O_(2)) and radicals(SO_(5)^(·-) and SO_(4)^(·-)) were involved in the reaction process and the SO_(5)^(·-)generated by the oxidation of PMS played a crucial role in the TCH degradation.The possible reaction mechanism was finally proposed.This study provided new insight into the Z-scheme heterostructure to promote the photo-assisted Fenton-like reaction.展开更多
Rechargeable batteries are essential for the increased demand for energy storage technologies due to their ability to adapt intermittent renewable energies into electric devices,such as electric vehicles.To boost the ...Rechargeable batteries are essential for the increased demand for energy storage technologies due to their ability to adapt intermittent renewable energies into electric devices,such as electric vehicles.To boost the battery performance,applying external fields to assist the electrochemical process has been developed and exhibits significant merits in energy efficiency and cycle stability enhancement.This perspective focuses on recent advances in the development of external field–assisted battery technologies,including photo-assisted,magnetic field–assisted,sound field–assisted,and multiple field–assisted.The workingmechanisms of external field–assisted batteries and their challenges and opportunities are highlighted.展开更多
Developing new catalysts to decorate photoelectrodes has been widely used to enhance the performance of photoelectrochemical(PEC)cells.However,the high cost,complex synthesis,and poor stability of catalyst decoration ...Developing new catalysts to decorate photoelectrodes has been widely used to enhance the performance of photoelectrochemical(PEC)cells.However,the high cost,complex synthesis,and poor stability of catalyst decoration strongly hinder its practical application.Here,we report a facile and low-cost decoration of Ag-Pt nanoparticles(Ag-Pt NPs)on Si photocathodes with TiO_(2)/Ti sacrificial overlayers.Such a decoration does not rely on any metallic-ion precursor solution since it is formed automatically via galvanic replacement reactions during PEC measurements;that is,Ti is displaced by Ag^(+)and Pt^(2+)ions,which are from the employed reference and counter electrodes,respectively.The as-decorated Ag-Pt NPs are verified to significantly enhance the hydrogen evolution reduction kinetics without substantially degrading the optical performance of Si photocathodes.Owing to optoelectronic advantages,the overpotential required to maintain a photocurrent density of 10 mA cm(under AM1.5 G illumination)is reduced from-0.8 V_(RHE)(for the bare planar Si photocathode)to-0.1 V_(RHE)(for the planar Si photocathode with Ag-Pt NP decoration).Moreover,a further anodic shift(to 0 V_(RHE))is visible for the Si nanowire array photocathode with Ag-Pt NP decoration,along with high long-term stability of the PEC response in acidic and neutral electrolytes.This study opens a new opportunity for the photo-assisted decoration of various alloy NPs on the morphology-varying photoelectrodes with different applications.展开更多
Oxygen reduction reaction(ORR)plays a pivotal role in advanced electrochemical energy conversion devices.However,the ORR conversion efficiency is extremely limited.The major obstacles originate from the adsorption and...Oxygen reduction reaction(ORR)plays a pivotal role in advanced electrochemical energy conversion devices.However,the ORR conversion efficiency is extremely limited.The major obstacles originate from the adsorption and activation of O_(2)on the electrode surface.A novel nanocomposite catalyst,photosensitizers(PS)meso-tetraphenylporphyrin iron(III)chloride(FePcCl)/NiCoFe-layered double hydroxides(NiCoFe-LDHs)is designed in this study.Herein,owing to excellent oxygen molecules activation ability and remarkable illumination absorption feature,FePcCl/NiCoFe-LDHs is employed to uncover the relationship between the intrinsic ORR activity and PS behaviour.Interestingly,the reaction mechanism of singlet 1O_(2)is proposed owing to the combination of electrochemical ORR catalysed via LDHs and PS.The boosted cathodic ORR properties exhibit singlet 1O_(2)dependent response arising from the synergistic effect to selectively produce active intermediates in alkaline medium.This work imparts the promising new mechanism about the high 4-electron ORR selectivity via material design,which will guide the development of photo-assisted energy conversion devices.展开更多
Electrochemical detection is an efficient method for the detection of Bisphenol A(BPA).Herein,a sensitive photo-electrochemical sensor based on two-dimensional(2 D)TiO_(2)(001)nanosheets was fabricated and then used f...Electrochemical detection is an efficient method for the detection of Bisphenol A(BPA).Herein,a sensitive photo-electrochemical sensor based on two-dimensional(2 D)TiO_(2)(001)nanosheets was fabricated and then used for BPA electrochemical detection.Upon light irradiation,the 2 D TiO_(2)(001)nanosheets electrode provided a lower detection limit of BPA detection compared with an ambient electrochemical determination.The low detection limit is^5.37 nmol/L(S/N=3).Furthermore,profiting from the photoelectric characteristics,the 2 D TiO_(2)(001)nanosheets electrode exhibits a nice regeneration prope rty.After 45 min of light irradiation,the electrochemical signal was regenerated from14.7%to 82.9%of the original signal at the 6th cycle.This is attributed to the non-selective·OH mediation produced by the 2 D TiO_(2)(001)nanosheets mineralizing anodic polymeric products and resuming surface reactive sites.This investigation indicates that photo-assistance is an efficient method to improve the electrochemical sensor for detecting BPA in water environments.展开更多
The energy crisis has always been a widely concerned problem. It is an urgent need for green and renewable energy technologies to achieve sustainable development, and the photo-assisted charging energy storage devices...The energy crisis has always been a widely concerned problem. It is an urgent need for green and renewable energy technologies to achieve sustainable development, and the photo-assisted charging energy storage devices provide a new way to realize the sustainable utilization of solar energy. Here, we fabricated a photo-assisted charging fibrous supercapacitor (NM2P1) with Ti_(3)C_(2)T_(x)-based hybrid fibre modified by nitrogen-doped carbon dots (NCDs). The NM2P1 fibre provides a volumetric capacitance of 1,445 F·cm^(−3) (630 F·g^(−1)) at 10 A·cm^(−3) under photo-assisted charging, which increases by 35.9% than that of dark condition (1,063 F·cm^(−3)/464 F·g^(−1)). Furthermore, the NM2P1 fibrous supercapacitor device shows that the maximum volumetric energy density and volumetric power density are 18.75 mWh·cm^(−3) and 8,382 mW·cm^(−3). Notably, the transient photovoltage (TPV) test was used to further confirm that NCDs as a photosensitizer enhance the light absorption capacity and faster charge transfer kinetics of NM2P1 fibre. This work directly exploits solar energy to improve the overall performance of supercapacitor, which opens up opportunities for the utilization of renewable energy and the development of photosensitive energy equipment.展开更多
Water splitting is important to the conversion and storage of renewable energy,but slow kinetics of the oxygen evolution reaction(OER)greatly limits its utility.Here,under visible light illumination,the p-n WO_(3)/SnS...Water splitting is important to the conversion and storage of renewable energy,but slow kinetics of the oxygen evolution reaction(OER)greatly limits its utility.Here,under visible light illumination,the p-n WO_(3)/SnSe_(2)(WS)heterojunction significantly activates OER catalysis of CoFe-layered double hydroxide(CF)/carbon nanotubes(CNTs).Specifically,the catalyst achieves an overpotential of 224 mV at 10 mA cm^(-2)and a small Tafel slope of 47 mV dec^(-1),superior to RuO_(2)and most previously reported transition metal-based OER catalysts.The p-n WS heterojunction shows strong light absorption to produce photogenerated carriers.The photogenerated holes are trapped by CF to suppresses the charge recombination and facilitate charge transfer,which accelerates OER kinetics and boost the activity for the OER.This work highlights the possibility of using heterojunctions to activate OER catalysis and advances the design of energy-efficient catalysts for water oxidation systems using solar energy.展开更多
Photo-assisted lithium-oxygen(Li-O_(2))batteries have been developed as a new system to reduce a large overpotential in the Li-O_(2)batteries.However,constructing an optimized photocatalyst is still a challenge to ach...Photo-assisted lithium-oxygen(Li-O_(2))batteries have been developed as a new system to reduce a large overpotential in the Li-O_(2)batteries.However,constructing an optimized photocatalyst is still a challenge to achieve broad light absorption and a low recombined rate of photoexcited electrons and holes.Herein,oxygen vacancy-rich molybdenum trioxide(MoO_(3-x))nanorods are employed as photocatalysts to accelerate kinetics of cathode reactions in the photo-assisted Li-O_(2)batteries.Oxygen vacancies on the MoO_(3-x)nanorods can not only increase light-harvesting capability but also improve electrochemical activity for the cathode reactions.Under illumination,the photoexcited electrons and holes are effectively separated on the MoO_(3-x)nanorods.During discharging,activated O2 is reduced to Li_(2)O_(2)by the photoexcited electrons from the MoO_(3-x)nanorods.The photoexcited holes can promote the decomposition of Li_(2)O_(2)during subsequent charging.Accordingly,the photo-assisted Li-O_(2)batteries with the MoO_(3-x)nanorods deliver an ultralow overpotential of 0.22 V,considerable rate capability,and good reversibility.We think that this work could give a reference for the exploitation and application of the photocatalysts in the photo-assisted Li-O_(2)batteries.展开更多
Solar cells hold a function of photovoltaic conversion,while rechargeable metal batteries have an advantage of high energy storage.The conventional charge mode of batteries is made based on complete utilization of ele...Solar cells hold a function of photovoltaic conversion,while rechargeable metal batteries have an advantage of high energy storage.The conventional charge mode of batteries is made based on complete utilization of electric energy.The combination of solar cells and rechargeable metal batteries brings a new opportunity for the development of photo-assisted rechargeable batteries,in which the solar energy can be utilized to partially achieve photo-charging with or without external electrical bias.This review highlights the working mechanism and structure design of photo-assisted rechargeable metal batteries according to the characteristics of rechargeable metal batteries and advantage of the photovoltaic technology.In particular,the recent advances are introduced for photo-assisted rechargeable batteries based on light-weight metal anodes,including metal lithium,metal sodium,and metal zinc.The working features of the integrated devices are also discussed for energy saving under photo-assisted charging mode.Finally,a future outlook is provided for further improving the performance of photoassisted rechargeable metal batteries.展开更多
Photo-assisted deposited method is often employed in the metal-organic chemical vapor deposition whose ion source is organic compounds. It has been proved to increase the deposition rate and improve the crystallinity ...Photo-assisted deposited method is often employed in the metal-organic chemical vapor deposition whose ion source is organic compounds. It has been proved to increase the deposition rate and improve the crystallinity of the films. We demonstrate a photo-assisted sputtering deposited method which is used to prepare high quality TiO_(2) films. The crystallinity of the films is improved by the photo assistance without changing the morphology. And the structural and optical properties remain the same. The photo-assisted deposited TiO_(2) film shows a H_(2) evolution rate of 1.62 μmol·cm^(-2)·h^(-1) that is about twice more than that of the pristine TiO_(2) film. It is found the Mott-Schottky effect responds for the photocatalytic activity. Photo-assisted deposited films show an enhanced photocatalytic activity due to the reduction of interface recombination and the high efficiency in the transferring of photo-generated carriers.展开更多
A series of experiments were conducted to systematically study the effects of etching conditions on GaN by a con-venient photo-assisted chemical （PAC） etching method. The solution concentration has an evident influe...A series of experiments were conducted to systematically study the effects of etching conditions on GaN by a con-venient photo-assisted chemical （PAC） etching method. The solution concentration has an evident influence on the surface morphology of GaN and the optimal solution concentrations for GaN hexagonal pyramids have been identified. GaN with hexagonal pyramids have higher crystal quality and tensile strain relaxation compared with as-grown GaN. A detailed anal- ysis about evolution of the size, density and optical property of GaN hexagonal pyramids is described as a function of light intensity. The intensity of photoluminescence spectra of GaN etched with hexagonal pyramids significantly increases compared to that of as-grown GaN due to multiple scattering events, high quality GaN with pyramids and the Bragg effect.展开更多
文摘以丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为起始原料,采用氧化还原/偶氮类复合引发体系,在金属卤化物灯的辅助下,制备了性能优良的阳离子聚丙烯酰胺(CPAM)。最佳反应条件下所得产物的特性粘数可达13.87 d L·g^(-1),溶解时间38 min。利用红外光谱(FTIR)、核磁共振氢谱(~1H-NMR)对产物的结构进行了详细表征。进一步研究了CPAM用量和特性粘数对其助留助滤性能的影响,并与国外同类产品进行了助留助滤性能比较。
基金supported by the National Natural Science Foundation of China(61904023 and 11974063)the Natural Science Foundation of Chongqing(cstc2019jcyj-bsh X0078)。
基金supported by the start-up grant of Central South University(No.202045001)the Huxiang Assembly Program for High-level Talents(Hunan Province,No.2018RS3018)the Innovation-Driven Program of Central South University(No.2019CX028).
文摘Transition metal sulfide-based hydrogen evolution electrocatalysts still lag in catalytic activity due to the zero-deviated free energy of*H adsorption.Plasmonic metals bridge the gap between light utilization and plasmon-mediated redox reactions for substantially enhanced electrocatalytic activity.In this work,a strategic broadband light utilization heterostructure,composed of two distinct Ag nanostructures(discontinuous Ag nanorods and monodispersed nanoparticles),is achieved through in situ sulfurization and metal leaching.The heterostructure benefits the electrocatalytic hydrogen evolution reactivity thanks to the localized surface plasmon resonance induced hot electrons injection and inter-gap electric fields revealed by the finite-difference time-domain simulation.Experimentally,the prudent heterostructured catalyst exhibits a significantly improved overpotential(at 10 mA cm−2)from 151 to 95 mV along with a Tafel slope from 74 to 45 mV dec−1 toward hydrogen evolution.Significantly,this instructional study sheds light on the design of hybrid photo-assisted electrocatalysts with cooperative effect of solar energy toward sustainable electrocatalysis.
基金financially supported by the National Natural Science Foundation of China(Nos.52170079 and U20A20322)the Programme of Introducing Talents of Discipline to Universities,China(No.B16020)。
文摘The Z-scheme heterostructure for photocatalyst can effectively prolong the lifetime of photogenerated carriers and retain a higher conduction/valence band position,promoting the synergistic coupling of photocatalysis and peroxymonosulfate(PMS) activation.In order to fully utilize the luminous energy and realize the efficient activation of PMS,this work achieved successful construction of NiCo_(2)O_(4)/BiOCl/Bi_(24)O_(31)Br_(10) ternary Z-scheme heterojunction by simultaneously synthesizing BiOCl and NiCo_(2)O_(4) with NiCl_(2) and CoCl_(2) as the precursors.The intercalated BiOCl could serve as a carrier migration ladder to further achieve the spatial separation of electron-hole pairs,so that the oxidation and reduction processes separately occurred in different regions.Compared with the reported catalysts,the as-prepared composites exhibited the enhanced removal efficiency for tetracycline hydrochloride(TCH) in the visible light/PMS system,with a degradation efficiency of 85.30%in 2 min,and possessed good stability.Z-scheme heterojunction was shown to be beneficial for maximizing the superiority of photo-assisted Fenton-like reaction system.The experimental and characterization results confirmed that both non-radicals(^(1)O_(2)) and radicals(SO_(5)^(·-) and SO_(4)^(·-)) were involved in the reaction process and the SO_(5)^(·-)generated by the oxidation of PMS played a crucial role in the TCH degradation.The possible reaction mechanism was finally proposed.This study provided new insight into the Z-scheme heterostructure to promote the photo-assisted Fenton-like reaction.
基金Innovation and Technology Commission of the Hong Kong Special Administrative Region,China,Grant/Award Number:ITS/219/21FP。
文摘Rechargeable batteries are essential for the increased demand for energy storage technologies due to their ability to adapt intermittent renewable energies into electric devices,such as electric vehicles.To boost the battery performance,applying external fields to assist the electrochemical process has been developed and exhibits significant merits in energy efficiency and cycle stability enhancement.This perspective focuses on recent advances in the development of external field–assisted battery technologies,including photo-assisted,magnetic field–assisted,sound field–assisted,and multiple field–assisted.The workingmechanisms of external field–assisted batteries and their challenges and opportunities are highlighted.
基金supported by the National Natural Science Foundation of China(62075146 and 61875143)the Natural Science Foundation of Jiangsu Province(BK20181169)+3 种基金the Natural Science Foundation of Jiangsu Higher Education Institutions(20KJA510003)Qinglan Project of Jiangsu Provincethe Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutionsthe Natural Science Research of Jiangsu Higher Education Institutions。
文摘Developing new catalysts to decorate photoelectrodes has been widely used to enhance the performance of photoelectrochemical(PEC)cells.However,the high cost,complex synthesis,and poor stability of catalyst decoration strongly hinder its practical application.Here,we report a facile and low-cost decoration of Ag-Pt nanoparticles(Ag-Pt NPs)on Si photocathodes with TiO_(2)/Ti sacrificial overlayers.Such a decoration does not rely on any metallic-ion precursor solution since it is formed automatically via galvanic replacement reactions during PEC measurements;that is,Ti is displaced by Ag^(+)and Pt^(2+)ions,which are from the employed reference and counter electrodes,respectively.The as-decorated Ag-Pt NPs are verified to significantly enhance the hydrogen evolution reduction kinetics without substantially degrading the optical performance of Si photocathodes.Owing to optoelectronic advantages,the overpotential required to maintain a photocurrent density of 10 mA cm(under AM1.5 G illumination)is reduced from-0.8 V_(RHE)(for the bare planar Si photocathode)to-0.1 V_(RHE)(for the planar Si photocathode with Ag-Pt NP decoration).Moreover,a further anodic shift(to 0 V_(RHE))is visible for the Si nanowire array photocathode with Ag-Pt NP decoration,along with high long-term stability of the PEC response in acidic and neutral electrolytes.This study opens a new opportunity for the photo-assisted decoration of various alloy NPs on the morphology-varying photoelectrodes with different applications.
基金the financial support from the Major State Basic Research Development Program of China(973 Program)(No.2014CB932101)the National Natural Science Foundation of China(Nos.21571013 and 52073023)Program for Chang Jiang Scholars and Innovative Research Team in University(No.IRT1205).
文摘Oxygen reduction reaction(ORR)plays a pivotal role in advanced electrochemical energy conversion devices.However,the ORR conversion efficiency is extremely limited.The major obstacles originate from the adsorption and activation of O_(2)on the electrode surface.A novel nanocomposite catalyst,photosensitizers(PS)meso-tetraphenylporphyrin iron(III)chloride(FePcCl)/NiCoFe-layered double hydroxides(NiCoFe-LDHs)is designed in this study.Herein,owing to excellent oxygen molecules activation ability and remarkable illumination absorption feature,FePcCl/NiCoFe-LDHs is employed to uncover the relationship between the intrinsic ORR activity and PS behaviour.Interestingly,the reaction mechanism of singlet 1O_(2)is proposed owing to the combination of electrochemical ORR catalysed via LDHs and PS.The boosted cathodic ORR properties exhibit singlet 1O_(2)dependent response arising from the synergistic effect to selectively produce active intermediates in alkaline medium.This work imparts the promising new mechanism about the high 4-electron ORR selectivity via material design,which will guide the development of photo-assisted energy conversion devices.
基金the Applied Basic Research Programs of Yunnan Science and Technology Department(No.2017FD085)the Program of Introducing Talents of Kunming University(Nos.YJL16003 and YJL18008)+4 种基金National Nature Science Foundation of China(No.61904073)Science Foundation of Yunnan Provincial Education Department(No.2018JS392)Projects of Science and Technology Plans of Kunming(No.20191-C-25318000002189)“Thousand Talents Program”of Yunnan Province for Young TalentsSpring City Plan-Special Program for Young Talents。
文摘Electrochemical detection is an efficient method for the detection of Bisphenol A(BPA).Herein,a sensitive photo-electrochemical sensor based on two-dimensional(2 D)TiO_(2)(001)nanosheets was fabricated and then used for BPA electrochemical detection.Upon light irradiation,the 2 D TiO_(2)(001)nanosheets electrode provided a lower detection limit of BPA detection compared with an ambient electrochemical determination.The low detection limit is^5.37 nmol/L(S/N=3).Furthermore,profiting from the photoelectric characteristics,the 2 D TiO_(2)(001)nanosheets electrode exhibits a nice regeneration prope rty.After 45 min of light irradiation,the electrochemical signal was regenerated from14.7%to 82.9%of the original signal at the 6th cycle.This is attributed to the non-selective·OH mediation produced by the 2 D TiO_(2)(001)nanosheets mineralizing anodic polymeric products and resuming surface reactive sites.This investigation indicates that photo-assistance is an efficient method to improve the electrochemical sensor for detecting BPA in water environments.
基金This work is supported by National MCF Energy R&D Program (No. 2018YFE0306105)the National Key Research and Development Project of China (No. 2020YFA0406104)+4 种基金Innovative Research Group Project of the National Natural Science Foundation of China (No. 51821002)the National Natural Science Foundation of China (Nos. 51725204, 21771132, 51972216, and 52041202)Natural Science Foundation of Jiangsu Province (No. BK20190041)Key-Area Research and Development Program of GuangDong Province (No. 2019B010933001)Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), and the 111 Project.
文摘The energy crisis has always been a widely concerned problem. It is an urgent need for green and renewable energy technologies to achieve sustainable development, and the photo-assisted charging energy storage devices provide a new way to realize the sustainable utilization of solar energy. Here, we fabricated a photo-assisted charging fibrous supercapacitor (NM2P1) with Ti_(3)C_(2)T_(x)-based hybrid fibre modified by nitrogen-doped carbon dots (NCDs). The NM2P1 fibre provides a volumetric capacitance of 1,445 F·cm^(−3) (630 F·g^(−1)) at 10 A·cm^(−3) under photo-assisted charging, which increases by 35.9% than that of dark condition (1,063 F·cm^(−3)/464 F·g^(−1)). Furthermore, the NM2P1 fibrous supercapacitor device shows that the maximum volumetric energy density and volumetric power density are 18.75 mWh·cm^(−3) and 8,382 mW·cm^(−3). Notably, the transient photovoltage (TPV) test was used to further confirm that NCDs as a photosensitizer enhance the light absorption capacity and faster charge transfer kinetics of NM2P1 fibre. This work directly exploits solar energy to improve the overall performance of supercapacitor, which opens up opportunities for the utilization of renewable energy and the development of photosensitive energy equipment.
基金the National Natural Science Foundation of China(No.41807213)the Hydrogeo-logical Survey Project of Huangshui River(No.DD20190331).
文摘Water splitting is important to the conversion and storage of renewable energy,but slow kinetics of the oxygen evolution reaction(OER)greatly limits its utility.Here,under visible light illumination,the p-n WO_(3)/SnSe_(2)(WS)heterojunction significantly activates OER catalysis of CoFe-layered double hydroxide(CF)/carbon nanotubes(CNTs).Specifically,the catalyst achieves an overpotential of 224 mV at 10 mA cm^(-2)and a small Tafel slope of 47 mV dec^(-1),superior to RuO_(2)and most previously reported transition metal-based OER catalysts.The p-n WS heterojunction shows strong light absorption to produce photogenerated carriers.The photogenerated holes are trapped by CF to suppresses the charge recombination and facilitate charge transfer,which accelerates OER kinetics and boost the activity for the OER.This work highlights the possibility of using heterojunctions to activate OER catalysis and advances the design of energy-efficient catalysts for water oxidation systems using solar energy.
基金supported by the Jilin Province Science and Technology Department Program(Nos.YDZJ202101ZYTS047,YDZJ202201ZYTS304,20220201130GX,and 20200201187JC)the National Natural Science Foundation of China(Nos.52171210 and 21978110)the Science and Technology Project of Jilin Provincial EducationDepartment(Nos.JJJKH20210444KJ and JKH20220428KJ).
文摘Photo-assisted lithium-oxygen(Li-O_(2))batteries have been developed as a new system to reduce a large overpotential in the Li-O_(2)batteries.However,constructing an optimized photocatalyst is still a challenge to achieve broad light absorption and a low recombined rate of photoexcited electrons and holes.Herein,oxygen vacancy-rich molybdenum trioxide(MoO_(3-x))nanorods are employed as photocatalysts to accelerate kinetics of cathode reactions in the photo-assisted Li-O_(2)batteries.Oxygen vacancies on the MoO_(3-x)nanorods can not only increase light-harvesting capability but also improve electrochemical activity for the cathode reactions.Under illumination,the photoexcited electrons and holes are effectively separated on the MoO_(3-x)nanorods.During discharging,activated O2 is reduced to Li_(2)O_(2)by the photoexcited electrons from the MoO_(3-x)nanorods.The photoexcited holes can promote the decomposition of Li_(2)O_(2)during subsequent charging.Accordingly,the photo-assisted Li-O_(2)batteries with the MoO_(3-x)nanorods deliver an ultralow overpotential of 0.22 V,considerable rate capability,and good reversibility.We think that this work could give a reference for the exploitation and application of the photocatalysts in the photo-assisted Li-O_(2)batteries.
基金Financial supports from National Natural Science Foundation(21875123)of Chinathe project of Jiangxi Academy of Sciences(2020-YZD-3)are gratefully acknowledged.
文摘Solar cells hold a function of photovoltaic conversion,while rechargeable metal batteries have an advantage of high energy storage.The conventional charge mode of batteries is made based on complete utilization of electric energy.The combination of solar cells and rechargeable metal batteries brings a new opportunity for the development of photo-assisted rechargeable batteries,in which the solar energy can be utilized to partially achieve photo-charging with or without external electrical bias.This review highlights the working mechanism and structure design of photo-assisted rechargeable metal batteries according to the characteristics of rechargeable metal batteries and advantage of the photovoltaic technology.In particular,the recent advances are introduced for photo-assisted rechargeable batteries based on light-weight metal anodes,including metal lithium,metal sodium,and metal zinc.The working features of the integrated devices are also discussed for energy saving under photo-assisted charging mode.Finally,a future outlook is provided for further improving the performance of photoassisted rechargeable metal batteries.
基金the National Natural Science Foundation of China(61306075)。
文摘Photo-assisted deposited method is often employed in the metal-organic chemical vapor deposition whose ion source is organic compounds. It has been proved to increase the deposition rate and improve the crystallinity of the films. We demonstrate a photo-assisted sputtering deposited method which is used to prepare high quality TiO_(2) films. The crystallinity of the films is improved by the photo assistance without changing the morphology. And the structural and optical properties remain the same. The photo-assisted deposited TiO_(2) film shows a H_(2) evolution rate of 1.62 μmol·cm^(-2)·h^(-1) that is about twice more than that of the pristine TiO_(2) film. It is found the Mott-Schottky effect responds for the photocatalytic activity. Photo-assisted deposited films show an enhanced photocatalytic activity due to the reduction of interface recombination and the high efficiency in the transferring of photo-generated carriers.
基金Project supported by the National Basic Research Program of China(Grant Nos.2011CB301900,2012CB619304,and 2010CB327504)the National High Technology Research and Development Program of China(Grant No.2011AA03A103)+1 种基金the National Nature Science Foundation of China(Grant Nos.60990311,60906025,60936004,and 61176063)the Natural Science Foundation of Jiangsu Province,China(Grant Nos.BK2011010 and BK2009255)
文摘A series of experiments were conducted to systematically study the effects of etching conditions on GaN by a con-venient photo-assisted chemical （PAC） etching method. The solution concentration has an evident influence on the surface morphology of GaN and the optimal solution concentrations for GaN hexagonal pyramids have been identified. GaN with hexagonal pyramids have higher crystal quality and tensile strain relaxation compared with as-grown GaN. A detailed anal- ysis about evolution of the size, density and optical property of GaN hexagonal pyramids is described as a function of light intensity. The intensity of photoluminescence spectra of GaN etched with hexagonal pyramids significantly increases compared to that of as-grown GaN due to multiple scattering events, high quality GaN with pyramids and the Bragg effect.
