以高纯V2O5为原料,用SO2还原法制备VOSO4、锌-氨法制备V2(SO4)3,分别作为钒电池正、负极电解液的活性物质。对电解液的制备工艺进行了研究,同时对SO2还原V2O5的反应机理进行了研究,计算了制备VOSO4的反应焓变和吉布斯自由能变化,并对制...以高纯V2O5为原料,用SO2还原法制备VOSO4、锌-氨法制备V2(SO4)3,分别作为钒电池正、负极电解液的活性物质。对电解液的制备工艺进行了研究,同时对SO2还原V2O5的反应机理进行了研究,计算了制备VOSO4的反应焓变和吉布斯自由能变化,并对制备的电解液进行了电化学性能测试。结果表明:该法生产工艺简单,生产效率高,电解液浓度可任意调配;在电流密度为5.0 m A/cm2时,电池的电流效率、电压效率、能量效率分别为94.5%、91.2%和90.1%,满足钒电池电解液的性能要求。展开更多
This study systematically investigated the effects of experimental conditions,crystal phase,and microstructure on the preparation of V_(2)O_(3)for vanadium flow batteries by reducing ammonium metavanadate extracted fr...This study systematically investigated the effects of experimental conditions,crystal phase,and microstructure on the preparation of V_(2)O_(3)for vanadium flow batteries by reducing ammonium metavanadate extracted from waste catalyst.The optimized experimental conditions were determined as follows:the CO reduction temperature was set at 575℃,the reduction time was 1 hour,the CO flow rate was 50 mL/min,and furnace cooling was performed subsequently.Under these conditions,the samples obtained were predominantly composed of single-phase V_(2)O_(3).Microstructural analysis reveals tightly packed grain configurations exhibiting flake-like or block-like morphologies.Significantly,the as-synthesized V_(2)O_(3)demonstrates sufficient purity for fabricating high-performance electrolytes in all-vanadium flow batteries,showing promising electrochemical applicability.展开更多
Vanadium redox flow batteries(VRFBs)are one of the most promising energy storage systems owing to their safety,efficiency,flexibility and scalability.However,the commercial viability of VRFBs is still hindered by the ...Vanadium redox flow batteries(VRFBs)are one of the most promising energy storage systems owing to their safety,efficiency,flexibility and scalability.However,the commercial viability of VRFBs is still hindered by the low electrochemical performance of the available carbon-based electrodes.Defect engineering is a powerful strategy to enhance the redox catalytic activity of carbon-based electrodes for VRFBs.In this paper,uniform carbon defects are introduced on the surfaces of carbon felt(CF)electrode by Ar plasma etching.Together with a higher specific surface area,the Ar plasma treated CF offers additional catalytic sites,allowing faster and more reversible oxidation/reduction reactions of vanadium ions.As a result,the VRFB using plasma treated electrode shows a power density of 1018.3 mW/cm^(2),an energy efficiency(EE)of 84.5%,and the EE remains stable over 1000 cycles.展开更多
文摘以高纯V2O5为原料,用SO2还原法制备VOSO4、锌-氨法制备V2(SO4)3,分别作为钒电池正、负极电解液的活性物质。对电解液的制备工艺进行了研究,同时对SO2还原V2O5的反应机理进行了研究,计算了制备VOSO4的反应焓变和吉布斯自由能变化,并对制备的电解液进行了电化学性能测试。结果表明:该法生产工艺简单,生产效率高,电解液浓度可任意调配;在电流密度为5.0 m A/cm2时,电池的电流效率、电压效率、能量效率分别为94.5%、91.2%和90.1%,满足钒电池电解液的性能要求。
文摘This study systematically investigated the effects of experimental conditions,crystal phase,and microstructure on the preparation of V_(2)O_(3)for vanadium flow batteries by reducing ammonium metavanadate extracted from waste catalyst.The optimized experimental conditions were determined as follows:the CO reduction temperature was set at 575℃,the reduction time was 1 hour,the CO flow rate was 50 mL/min,and furnace cooling was performed subsequently.Under these conditions,the samples obtained were predominantly composed of single-phase V_(2)O_(3).Microstructural analysis reveals tightly packed grain configurations exhibiting flake-like or block-like morphologies.Significantly,the as-synthesized V_(2)O_(3)demonstrates sufficient purity for fabricating high-performance electrolytes in all-vanadium flow batteries,showing promising electrochemical applicability.
基金Project(Xiang Zu [2016] 91) supported by the “100 Talented Teams” of Hunan Province,ChinaProject(2018RS3077) supported by the Huxiang High-level Talents Program,China+2 种基金Project(22002009) supported by the National Natural Science Foundation of ChinaProject(2021JJ40565) supported by the Natural Science Foundation of Hunan Province,ChinaProject(19C0054) supported by the Scientific Research Foundation of Hunan Provincial Education Department,China。
文摘Vanadium redox flow batteries(VRFBs)are one of the most promising energy storage systems owing to their safety,efficiency,flexibility and scalability.However,the commercial viability of VRFBs is still hindered by the low electrochemical performance of the available carbon-based electrodes.Defect engineering is a powerful strategy to enhance the redox catalytic activity of carbon-based electrodes for VRFBs.In this paper,uniform carbon defects are introduced on the surfaces of carbon felt(CF)electrode by Ar plasma etching.Together with a higher specific surface area,the Ar plasma treated CF offers additional catalytic sites,allowing faster and more reversible oxidation/reduction reactions of vanadium ions.As a result,the VRFB using plasma treated electrode shows a power density of 1018.3 mW/cm^(2),an energy efficiency(EE)of 84.5%,and the EE remains stable over 1000 cycles.
