Suppressing Leakage Currents and Improving Performance of Indoor Organic Photovoltaic Devices.

Organic photovoltaic (OPV) devices hold great promise for indoor light harvesting, offering a theoretical upper limit of power conversion efficiency that surpasses that of other photovoltaic technologies. However, the presence of high leakage currents in OPV devices commonly constrains their effective performance under indoor conditions. In this study, we identified that the origin of the high leakage currents in OPV devices lay in pinhole defects present within the active layer (AL). By integrating an automated spin-coating strategy with sequential deposition processes, we achieved the compactness of the AL and minimized the occurrence of pinhole defects therein. Experimental findings demonstrated that with an increase in the number of deposition cycles, the density of pinhole defects in the AL underwent a marked reduction. Consequently, the leakage current experienced a substantial decrease by several orders of magnitude which achieved through well-calibrated AL deposition procedures. This enabled a twofold enhancement in the power conversion efficiency (PCE) of the OPV devices under conditions of indoor illumination. [ABSTRACT FROM AUTHOR]