Redox active and electrically conducting cobalt telluride Nanorods/Poly(1-aminoanthraquinone) composite and photoactive Rose Bengal dye based photo-supercapacitor

Abstract

Photo-supercapacitor (PSC) allows concurrent harvesting and storage of solar energy in a single device. Cost-effective and a highly scalable novel configuration for a PSC comprising of Rose Bengal (RB) dye/cadmium sulfide (CdS)/titania (TiO2) as the photovoltaic electrode and CoTe nanorods/poly(1-aminoanthraquinone) (PAAQ) composite/carbon fabric (C-fabric) as the counter electrode (CE) combined with PAAQ/C-fabric as the symmetric supercapacitor electrodes, is presented. The two low cost photosensitizers (RB dye and CdS) permit broad utilization of the solar spectrum (blue-green and to some extent, red photons as well), and the CoTe/PAAQ composite offers a high electrocatalytic activity for polysulfide reduction, resulting in a power conversion efficiency of 8.25%. The composite as a CE outperforms the individual CEs of CoTe and PAAQ. When the illuminated solar cell is electrically connected to the PAAQ//PAAQ supercapacitor, the latter is charged to 0.77 V and it acquires an areal specific capacitance of 79.2 m F cm−2 under a galvanostatic discharge current density of 0.07 mA cm−2. This PSC shows an overall photo-electrical conversion and storage efficiency of 4.68% and it serves as a promising solution for integrating solar conversion and storage in a single device.