A kind of dispersed electrode was prepared by electrodeposition technique.The factors of affecting the electrodeposition were discussed and the electromotive force of the dispersion cell was measured this paper.The re...A kind of dispersed electrode was prepared by electrodeposition technique.The factors of affecting the electrodeposition were discussed and the electromotive force of the dispersion cell was measured this paper.The results shows that there are obvious effects of quantity of addictives,the current density and temperature on the dispersivity of the dispersed electrode,and that there indeed exists a potential difference between two electrodes of the same material with different dispersivity,namely the electromotive force of a dispersion cell.It was concluded that and the greater difference of the dispersivities between the two electrodes,the greater electromotive force of the dispersion cell.展开更多
A new additive of sodium hexametaphosphate （SHMP） was introduced to the paste of zinc electrode, with the purpose of preventing the zinc active materials from agglomerating and improving the stability of batteries. ...A new additive of sodium hexametaphosphate （SHMP） was introduced to the paste of zinc electrode, with the purpose of preventing the zinc active materials from agglomerating and improving the stability of batteries. The properties of the zinc electrodes were characterized by scanning electron microscopy （SEM）, constant current charge/discharge measurement, self-discharge test and hydrogen collection experiment. The photographs of zinc electrode show that SHMP can significantly break up the agglomeration, uniforrnize the particle distribution and increase the surface area, which are advantageous to improve the electrochemical performance of zinc electrode. The experimental battery shows a 97 times cycling life and a 30.2% remaining capacity after 4 d storage. The hydrogen collection experimental results indicate that the SHMP can decrease the ratio of hydrogen evolution. Therefore, the corrosion of zinc electrode is suppressed and the charge/discharge efficiency is enhanced.展开更多
Anatase Ti0_(2) nanosheet-based hierarchical spheres(HSs)with nearly 100%exposed{001}facets were synthesized via a facile solvothermal process.Using these hierarchical spheres as a scattering layer on nanocrystaline T...Anatase Ti0_(2) nanosheet-based hierarchical spheres(HSs)with nearly 100%exposed{001}facets were synthesized via a facile solvothermal process.Using these hierarchical spheres as a scattering layer on nanocrystaline TiO_(2)film,hi-layered dye-sensitized solar cells(DSSCs)have been fabricated by electrophoresis deposition method,which well preserved the fragile hierarchical structure.Owing to the superior dye adsorption and light scattering effect of HSs,an overall energy conversion efficiency of 7.38%is achieved,which is 26%higher than that of nanoparticle-based photoanode.展开更多
Density functional theory calculations and ab initio molecular dynamics simulations are performed to study the feasibility of using borophene, a newly synthesized two-dimensional sheet of boron, as an anode material f...Density functional theory calculations and ab initio molecular dynamics simulations are performed to study the feasibility of using borophene, a newly synthesized two-dimensional sheet of boron, as an anode material for sodium-ion and sodium-oxygen batteries. The theo- retical capacity of borophene is found to be as high as 1,218 mAh g-1 （Nao.sB）. More importantly, it is demonstrated that the sodium diffusion energy barrier along the valley direction is as low as 0.0019 eV, which corresponds to a diffusivity of more than a thousand times higher than that of conventional anode materials such as Na2Ti307 and Na3Sb. Hence, the use of borophene will revolutionize the rate capability of sodium-based batteries. Moreover, it is predicted that, during the sodiation process, the average open-circuit voltage is 0.53 V, which can effectively sup- press the formation of dendrites while maximizing the energy density. The metallic feature and structural integrity of borophene can be well preserved at different sodium concentrations, demonstrating good electronic conductivity and stable cyclability.展开更多
Generally, nanoparticles are easy to aggregate due to their nano sizes, which influence the physical and chemical properties. In this work, a dispersion treatment of the TiO2 nanoparticles with different average sizes...Generally, nanoparticles are easy to aggregate due to their nano sizes, which influence the physical and chemical properties. In this work, a dispersion treatment of the TiO2 nanoparticles with different average sizes was employed to improve the disper- sion of TiO2 nanoparticles, in order to prepare flexible photoanodes for dye-sensitized solar cells （DSCs） with novel photovol- talc properties at a low temperature. The effects of dispersion treatment on the dispersion of TiO2 nanoparticles, including the viscosities of the binder-free TiO2 paste, the morphologies and textural properties of nanoparticle-TiO2 films, and the photo- voltaic properties of the flexible DSCs, were investigated. Flexible indium-tin oxide （ITO）-coated polyethylene naphthalate （PEN） substrates with sputter deposited Pt were employed as the transparent flexible counter electrodes. A short-circuit photo- current density of 9.62 mA·cm^-2, an open-circuit voltage of 0.757 V, a fill factor of 0.589 and an overall light-to-energy con- version efficiency of 4.29% for the flexible DSCs under AM1.5 illumination of 100 mW·cm^-2 were obtained with dispersion treatment. A 30.8% increment of the energy conversion efficiency for DSCs made by dispersion treatment was obtained com- pared with that made without dispersion treatment.展开更多
Ti O2 nanowire(NW) is one of the potential scattering layer materials in dye-sensitized solar cells(DSSCs) owing to its fast electron conductivity and excellent light scattering property resulting from its one-dimensi...Ti O2 nanowire(NW) is one of the potential scattering layer materials in dye-sensitized solar cells(DSSCs) owing to its fast electron conductivity and excellent light scattering property resulting from its one-dimensional(1D) morphology. However, Ti O2 NWs used as scattering layers in previous work were either aggregated or shortened into shuttles that cannot use their unique 1D properties. In this paper, we present the preparation of a well-dispersed long NW paste(exceeding 1 ?m) by a mild method and used as a scattering layer in DSSC. The paste achieved a photoconversion efficiency of 5.73% and an efficiency enhancement of 12% compared with commercial scattering layer(P200 paste). Compared with the DSSC without a scattering layer, an efficiency enhancement of 54.9% was achieved. Also, the largest efficiency of 6.89% was obtained after optimization of photoanode thickness. The photoanodes were investigated through dye desorbed experiments and transmission spectra, which suggested that P25 nanoparticles with the as-prepared NW scattering layer loaded more dye than those with P200 paste. These results indicate that well-dispersed long NW paste has a potential application in scattering layers.展开更多
文摘A kind of dispersed electrode was prepared by electrodeposition technique.The factors of affecting the electrodeposition were discussed and the electromotive force of the dispersion cell was measured this paper.The results shows that there are obvious effects of quantity of addictives,the current density and temperature on the dispersivity of the dispersed electrode,and that there indeed exists a potential difference between two electrodes of the same material with different dispersivity,namely the electromotive force of a dispersion cell.It was concluded that and the greater difference of the dispersivities between the two electrodes,the greater electromotive force of the dispersion cell.
基金Project(2006BAE03B03) supported by the National Key Technologies Research and Development Program of China
文摘A new additive of sodium hexametaphosphate （SHMP） was introduced to the paste of zinc electrode, with the purpose of preventing the zinc active materials from agglomerating and improving the stability of batteries. The properties of the zinc electrodes were characterized by scanning electron microscopy （SEM）, constant current charge/discharge measurement, self-discharge test and hydrogen collection experiment. The photographs of zinc electrode show that SHMP can significantly break up the agglomeration, uniforrnize the particle distribution and increase the surface area, which are advantageous to improve the electrochemical performance of zinc electrode. The experimental battery shows a 97 times cycling life and a 30.2% remaining capacity after 4 d storage. The hydrogen collection experimental results indicate that the SHMP can decrease the ratio of hydrogen evolution. Therefore, the corrosion of zinc electrode is suppressed and the charge/discharge efficiency is enhanced.
文摘Anatase Ti0_(2) nanosheet-based hierarchical spheres(HSs)with nearly 100%exposed{001}facets were synthesized via a facile solvothermal process.Using these hierarchical spheres as a scattering layer on nanocrystaline TiO_(2)film,hi-layered dye-sensitized solar cells(DSSCs)have been fabricated by electrophoresis deposition method,which well preserved the fragile hierarchical structure.Owing to the superior dye adsorption and light scattering effect of HSs,an overall energy conversion efficiency of 7.38%is achieved,which is 26%higher than that of nanoparticle-based photoanode.
基金supported by a Grant from the Research Grants Council of the Hong Kong Special Administrative Region,China(16213414)
文摘Density functional theory calculations and ab initio molecular dynamics simulations are performed to study the feasibility of using borophene, a newly synthesized two-dimensional sheet of boron, as an anode material for sodium-ion and sodium-oxygen batteries. The theo- retical capacity of borophene is found to be as high as 1,218 mAh g-1 （Nao.sB）. More importantly, it is demonstrated that the sodium diffusion energy barrier along the valley direction is as low as 0.0019 eV, which corresponds to a diffusivity of more than a thousand times higher than that of conventional anode materials such as Na2Ti307 and Na3Sb. Hence, the use of borophene will revolutionize the rate capability of sodium-based batteries. Moreover, it is predicted that, during the sodiation process, the average open-circuit voltage is 0.53 V, which can effectively sup- press the formation of dendrites while maximizing the energy density. The metallic feature and structural integrity of borophene can be well preserved at different sodium concentrations, demonstrating good electronic conductivity and stable cyclability.
基金supported by the National High Technology Research and Development Program of China (Grant No. 2011AA-050522)Sanjiang-yuan Scientific Program of Qinghai Science & Technology Department(Grant No. 2010-N-S03)the Ministry of Science & Technology (MOST) International S&T Cooperation Program of China (Grant No. 2010DFA-64360)
文摘Generally, nanoparticles are easy to aggregate due to their nano sizes, which influence the physical and chemical properties. In this work, a dispersion treatment of the TiO2 nanoparticles with different average sizes was employed to improve the disper- sion of TiO2 nanoparticles, in order to prepare flexible photoanodes for dye-sensitized solar cells （DSCs） with novel photovol- talc properties at a low temperature. The effects of dispersion treatment on the dispersion of TiO2 nanoparticles, including the viscosities of the binder-free TiO2 paste, the morphologies and textural properties of nanoparticle-TiO2 films, and the photo- voltaic properties of the flexible DSCs, were investigated. Flexible indium-tin oxide （ITO）-coated polyethylene naphthalate （PEN） substrates with sputter deposited Pt were employed as the transparent flexible counter electrodes. A short-circuit photo- current density of 9.62 mA·cm^-2, an open-circuit voltage of 0.757 V, a fill factor of 0.589 and an overall light-to-energy con- version efficiency of 4.29% for the flexible DSCs under AM1.5 illumination of 100 mW·cm^-2 were obtained with dispersion treatment. A 30.8% increment of the energy conversion efficiency for DSCs made by dispersion treatment was obtained com- pared with that made without dispersion treatment.
基金supported by the National Basic Research Program of China(2011CB933002,2012CB932702)the National Natural Science Foundation of China(61306079,60871002)
文摘Ti O2 nanowire(NW) is one of the potential scattering layer materials in dye-sensitized solar cells(DSSCs) owing to its fast electron conductivity and excellent light scattering property resulting from its one-dimensional(1D) morphology. However, Ti O2 NWs used as scattering layers in previous work were either aggregated or shortened into shuttles that cannot use their unique 1D properties. In this paper, we present the preparation of a well-dispersed long NW paste(exceeding 1 ?m) by a mild method and used as a scattering layer in DSSC. The paste achieved a photoconversion efficiency of 5.73% and an efficiency enhancement of 12% compared with commercial scattering layer(P200 paste). Compared with the DSSC without a scattering layer, an efficiency enhancement of 54.9% was achieved. Also, the largest efficiency of 6.89% was obtained after optimization of photoanode thickness. The photoanodes were investigated through dye desorbed experiments and transmission spectra, which suggested that P25 nanoparticles with the as-prepared NW scattering layer loaded more dye than those with P200 paste. These results indicate that well-dispersed long NW paste has a potential application in scattering layers.
