电化学掺杂法处理的TiO2纳米管阵列电极.ppt

上海大学物理系 High-performance and renewable supercapacitors based on TiO2nanotube array electrodes treated by electrochemical doping approach Introduction Experimental details ?Preparation of TiO2 nanotube arrays ?Electrochemical doping of TiO2 nanotube films ?Assembly of supercapacitor devices Results and discussion Conclusion Introduction Strengths of anodic TiO2 nanotube arrays:light harvesting, electrochromic switching, energy storage devices, high surface area, excellent chemical stability ; Vertically oriented TiO2 nanotube arrays provide a direct pathway for electron transport along the long axis of nanotubes to the Ti foil substrate. Shortcomings of TiO2 nanotube arrays: wide bandgap ,poor capacitive behavior, limited conductivity. Therefore, substantial improvement in conductivity of TiO2 is needed for supercapacitor electrode materials. Before: Unpractically!! Introducing metal or nonmetal impurities;Consequently, numerous research concerning the doping or modification of TiO2 material ---- expensive facilities, or high processing temperatures, or a long duration process. Experimental detailsPreparation of TiO2 nanotube arrays Electrochemical doping of TiO2 nanotube films Assembly of supercapacitor devices Symmetric supercapacitors : Two identical pieces of TiO2-H electrodes were sandwiched by a glass fibre separator which was soaked with 2M Li2SO4 aqueous solution . Assess renewability of the supercapacitors： The TiO2-H electrodes were taken out from the devices after 2500 charge-discharge cycles and re-doped. Then the supercapacitors were reassembled by employing the re-doped TiO2-H electrodes and the same cycle-life tests were carried out again. Results and discussion FESEM;XRD;DXR AUTOLAB PGSTAT302 N/FRA2：CV;galvano-static charge-discharge tests; EIS Cycling stability test Cycling stability test Conclusion He have reported a facile and cost-effective