Flexible ITO films with atomically flat surfaces for high performance flexible perovskite solar cells.

We report high performance flexible Sn-doped In2O3 (ITO) films prepared by in-line type vertical plasma arc ion plating for high performance flexible perovskite solar cells. Even at room temperature deposition, the ion-plated ITO film showed a low sheet resistance of 15.75 Ohm per square, a high average optical transmittance of 85.88% and a small outer bending radius of 5 mm because energetic ITO ions accelerated to the substrate led to better crystallinity and adhesion than sputtered ITO films. In addition, the ion-plated ITO films showed atomically flat and smooth surfaces due to different growth mechanisms and the absence of resputtering effects during the ion plating process. Flexible perovskite solar cells fabricated on the ion-plated ITO electrodes showed a higher power conversion efficiency of 16.8% than the sputtered ITO-based perovskite solar cell, indicating the potential of ion plated ITO films as promising flexible and transparent electrodes for perovskite solar cells.

Roll-to-roll sputtered and patterned Cu2-x O/Cu/Cu2-x O multilayer grid electrode for flexible smart windows.

We fabricated cost-effective Cu2-x O/Cu/Cu2-x O multilayer grid electrodes using roll-to-roll (RTR) sputtering and patterning processes for use as transparent and flexible electrodes in flexible smart windows. To optimize the patterned Cu2-x O/Cu/Cu2-x O multilayer grid, the electrical and optical properties of the Cu2-x O/Cu/Cu2-x O multilayer grid electrodes were investigated as a function of grid width and pitch, which directly influence the filling factor of the grid. At the optimized grid width of 16 and pitch of 600 µm, the Cu2-x O/Cu/Cu2-x O multilayer grid had a sheet resistance of 7.17 Ohm per square and an optical transmittance of 87.6%. In addition, the mechanical properties of the optimized Cu2-x O/Cu/Cu2-x O multilayer grid electrode was compared to those of brittle ITO electrodes to demonstrate its outstanding flexibility. To show the potential of the Cu2-x O/Cu/Cu2-x O multilayer grid for smart windows, we fabricated a flexible and transparent thin film heater (TFH) and a flexible electrochromic (EC) device, which are key components of smart windows. The low saturation voltage of the Cu2-x O/Cu/Cu2-x O grid-based TFH and the fast on-off performance of the Cu2-x O/Cu/Cu2-x O grid-based EC device indicates that the RTR-processed Cu2-x O/Cu/Cu2-x O multilayer grid is promising as a low-cost and large-area flexible transparent electrode for high-performance smart windows.