Red Phosphorus and Sulfur-Doped Graphitic Carbon-Nitride Integrated with N-Doped Zno Nanorods as Photoanode for High Performance Dye-Sensitized Solar Cells

Abstract

In this study, nitrogen-doped zinc oxide/red phosphorus (RP)-doped graphitic carbon nitride (NZnO-PCN) has been introduced as a photoanode in dye-sensitized solar cells. The incorporation of RP into g-C₃N₄ has been shown to reduce its bandgap, thereby enhancing visible light absorption and improving light-harvesting efficiency. The doping of RP into g-C₃N₄ introduces localized electronic states within the g-C₃N₄ bandgap and facilitating efficient charge separation. As a result, the modified g-C₃N₄ exhibits enhanced light absorption and superior photocatalytic activity. At the same time, nitrogen doping in ZnO modifies its electronic structure, enhancing charge transport and suppressing recombination losses. The synergy between RP-doped g-C₃N₄ and NZnO creates an efficient heterojunction that enables seamless charge transfer and enhances photocatalytic performance. The resulting NZnO-PCN composite has a high specific surface area of 165.6 m² g⁻¹, which maximizes dye adsorption and interaction, further enhancing device performance. The optimized photoanode exhibits a power conversion efficiency of 8.8%, accompanied by a short-circuit current density (Jsc) of 20.50 mA cm⁻², an open-circuit voltage (V_oc) of 0.67 V, and a fill factor of 0.64. These results underscore the potential of RP-doped g-C₃N₄ coupled with NZnO as a state-of-the-art photoanode material for solar energy conversion devices.