Efficiency enhancement in dye-sensitized solar cells through neodymium-doped graphene quantum dot-modified TiO₂ photoanodes
- Authors:G.K.R. Senadeera, W.M.S.K. Weerasekara, T. Jaseetharan, P.U. Sandunika, J.M.K.W. Kumari, M.A.K.L. Dissanayake, Mohammad Muhiuddin, Mohammad Rizwan Rahman, Udaya Bhat K, Mohammad Waseem Akhtar, Udaya Kumar, A.B. Siddique, Piyasiri Ekanayake
- Publication Date:January 2, 2025
- Type:Journal Article
- DOI:10.1016/j.physb.2024.416797
- Publication On:Physica B: Condensed Matter
Abstract
This study explored the effects of Neodymium-doped graphene quantum dots (NdGQDs) on improving the performance efficiency of TiO2 based dye-sensitized solar cells (DSSCs). By employing in-situ physical assisted mixing, DSSCs with optimized NdGQDs in TiO2 photoanodes showed a power conversion efficiency of 8.76 %, a significant improvement compared to the 6.01 % efficiency of pristine TiO2-based DSSCs under 100 mW cm⁻2 illumination (AM 1.5). Notably, the short-circuit current density increased by 74 %. HRTEM analysis revealed that the NdGQDs have a size range of approximately 7–9 nm. UV–visible spectroscopy and Mott-Schottky analysis revealed a positive shift in the Fermi level, promoting better electron transfer and increased photocurrent density at the expenses of the open circuit voltage. Electrochemical impedance spectroscopy characterization of DSSCs incorporating NdGQD-modified photoanodes revealed a reduction in electron transfer resistance at the photoanode|dye|electrolyte interface, accompanied by an increase in recombination resistance within the device suppressing the electron recombination rate.