Sharma Meenakshi, Adalati Ravikant, Kumar Ashwani, Mehta Manan, Chandra Ramesh
Nano Science Laboratory, Institute Instrumentation Centre, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
ACS Appl Mater Interfaces. 2022 Jun 3. doi: 10.1021/acsami.2c05189.
Simultaneously achieving a transparent and high-energy density supercapacitor is a major challenge because of the trade-off between energy storage capacity and optical transparency of active electrode materials. Herein, we demonstrate a novel approach to construct an optically transparent asymmetric supercapacitor (Trans-ASC) by assembling positive (ZnO-SnO) and negative (TiO-SnO) composite thin-film electrodes on a conductive indium-doped tin oxide substrate via reactive DC magnetron cosputtering. The optical transmittance for both composite thin films is found to be 68% (ZnO-SnO) and 64% (TiO-SnO). Furthermore, electrochemical kinematics of the primed transparent electrodes are scrutinized in 0.5 M KOH electrolyte without affecting the transparency of active electrodes. The structural reliability of the electrodes aids the superb electrochemical performance to construct a Trans-ASC, TiO-SnO//ZnO-SnO, which works at a voltage of +1.2 V and attains a higher areal capacitance of 44.6 mF cm at 2 mA cm. The assembled Trans-ASC delivers a maximum areal energy density of 8.75 μW h cm with an optimal areal power density of 570 μW cm. Additionally, the capacitance retention of 81.6% and transparency of both electrodes remain almost the same (up to 60% for ZnO-SnO and 62% for TiO-SnO) even after 10,000 charging-discharging cycles. These remarkable electrochemical properties and outstanding cycling stability of the designed Trans-ASC device make it a potential candidate for storing energy and for further use in transparent electronic devices.
由于活性电极材料的储能容量和光学透明度之间存在权衡，同时实现透明且高能量密度的超级电容器是一项重大挑战。在此，我们展示了一种新颖的方法，通过反应性直流磁控共溅射在导电铟掺杂氧化锡衬底上组装正（ZnO-SnO）和负（TiO-SnO）复合薄膜电极，构建了一种光学透明的不对称超级电容器（Trans-ASC）。发现两种复合薄膜的光学透过率分别为68%（ZnO-SnO）和64%（TiO-SnO）。此外，在不影响活性电极透明度的情况下，在0.5 M KOH电解液中仔细研究了预处理透明电极的电化学动力学。电极的结构可靠性有助于构建Trans-ASC（TiO-SnO//ZnO-SnO）时展现出卓越的电化学性能，该超级电容器在+1.2 V的电压下工作，在2 mA cm时具有44.6 mF cm的更高面积电容。组装好的Trans-ASC在570 μW cm的最佳面积功率密度下提供8.75 μW h cm的最大面积能量密度。此外，即使经过10000次充放电循环，电容保持率为81.6%，且两个电极的透明度几乎保持不变（ZnO-SnO高达60%，TiO-SnO高达62%）。所设计的Trans-ASC器件的这些卓越电化学性能和出色的循环稳定性使其成为储能以及在透明电子器件中进一步应用的潜在候选者。
