Photoactive Core–Shell Nanorods as Bifunctional Electrodes for Boosting the Performance of Quantum Dot Sensitized Solar Cells and Photoelectrochemical Cells

Abstract

The performance of solar energy conversion and storage devices is contingent to the appropriate design of photosensitizers that make the electrodes. In quantum dot sensitized solar cells (QDSSCs) the power conversion efficiency (PCE) is mainly limited by the impediments of electron–hole pair generation in the trap state abundant QDs at the photoanode and below expected catalytic activity of the counter electrode (CE). Employing photoactive CEs, that too with precisely tuned core/shell nanorods (NRs) array is thereby a new approach in addressing these limitations. Herein CdS/Cu2S core/shell p-n junction NRs increase photon harvesting over a wider solar spectrum as well as demonstrate enhanced catalytic activity to reduce the oxidized polysulfide electrolyte. The NRs were also employed as photoanodes in photoelectrochemical (PEC) water splitting. The NRs with varying shell thickness were synthesized by meticulously controlled cation exchange and their vertical c-axis orientation not only offers high surface...