LaMnO₃ perovskite oxide has got tremendous attraction in electrochemical field owing to their favourable physical and chemical properties. However, aggregated and distorted morphology of regular perovskites that are prepared at higher temperatures (>500 °C) led to lesser active sites provided to enable the electrochemical reaction. Here we propose a green synthetic approach to overcome these deficiencies and to obtain better electrochemical performance. 3D polyhedron structured LaMnO₃ nanoparticles are synthesized using natural lemon juice (LJ) as a green surfactant. The aggregation of these particles is removed and a well separated individual particle has been formed. This well defined polyhedron structured LMO nanoparticle possessed a 3 fold enhancement in its specific capacitance. A symmetric two electrode cell system has also been fabricated to investigate the real life application of LMO as a supercapacitor. The electrode in this symmetric cell configuration could deliver a maximum energy density of 52.5 Wh kg^-1 at a power density of 1000 W kg^-1. This is an outstanding result among aqueous electrolyte symmetric supercapacitors. Moreover, the room temperature fluctuation effect on the specific capacitance of LMO cell has also been investigated. This LJ assisted synthesize of LMO perovskite presented here enlighten a simple paradigm for fabricating high energy electrochemical storage devices.

LaMnO ₃钙钛矿氧化物由于其良好的物理和化学性质而在电化学领域具有巨大的吸引力。但是，在较高温度（> 500°C）下制备的规则钙钛矿的聚集和扭曲形貌导致提供的较少活性位点能够进行电化学反应。在这里，我们提出了一种绿色的合成方法来克服这些缺陷并获得更好的电化学性能。3D多面体结构的LaMnO ₃使用天然柠檬汁（LJ）作为绿色表面活性剂合成纳米颗粒。这些颗粒的聚集被去除，并且已经形成了良好分离的单个颗粒。这种定义明确的多面体结构的LMO纳米颗粒的比电容提高了3倍。还制作了对称的两电极电池系统，以研究LMO作为超级电容器在现实生活中的应用。这种对称电池配置中的电极在1000 W kg ^-1的功率密度下可提供52.5 Wh kg ^-1的最大能量密度。这在水性电解质对称超级电容器中是一个杰出的结果。此外，还研究了室温波动对LMO电池比电容的影响。本文介绍的这种LJ辅助合成的LMO钙钛矿启发了制造高能电化学存储设备的简单范例。