Motlan, K. Sinulingga, N. Siregar
The global transition toward sustainable energy demands low-cost, eco-friendly photovoltaic technologies accessible to developing economies. This work addresses this challenge by preparing and characterizing Sb-doped ZnO thin films via sol-gel spin coating, evaluated as photoanodes in Dye-Sensitized Solar Cells (DSSCs) sensitised with purple sweet potato (Ipomoea batatas) anthocyanin, directly supporting SDG 7 (Affordable and Clean Energy). Films containing 2.0 to 4.0 wt% Sb were deposited on FTO substrates and annealed between 400 and 600°C. XRD confirmed a hexagonal wurtzite crystal structure with grain dimensions growing from 17.76 nm at 400°C to 28.39 nm at 600°C. SEM revealed well-formed hexagonal nanoparticle surfaces, and EDS validated successful Sb integration. UV-Vis analysis showed a thermally adjustable bandgap spanning 3.35 to 3.41 eV, with peak optical properties at 550°C. Photovoltaic testing demonstrated that 3.5 wt% Sb achieved the highest power conversion efficiency of 0.453% (Voc = 0.64 V, Jsc = 1.20 mA/cm², FF = 59.0%), representing a 43% improvement over the 2.0 wt% Sb reference (0.316%). These findings establish clear composition-structure-performance relationships for Sb-doped ZnO photoanodes with natural sensitizers, providing a foundational framework for future advances in sustainable, low-cost solar cell development for energy-scarce communities. © 2026, Rasayan Journal of Chemistry, c/o Dr. Pratima Sharma. All rights reserved.
Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Medan, North Sumatra, Medan, Indonesia
