Manganese (Mn) doping effects on the structure and surface characteristics of copper zinc tin sulphide (CZTS) transition metal sulphides synthesised via a sol–gel method

, respectively. Raman analysis verified a stannite-dominant structure, with red shifts corroborating the XRD findings. Although the surface areas and pore volume of CZTS samples decreased upon Mn doping, the pore size showed a notable increase. In addition, the particle size distribution ranged between 1 and 2 µm, and the zeta potential shifted from a net negative to a net positive charge, thereby enhancing the charge mobility after Mn doping. Scanning electron micrographs revealed reduced particle agglomeration, improved grain size, and surface uniformity following Mn doping, while energy-dispersive X-ray analysis confirmed the successful Mn substitution into the CZTS in all samples. In conclusion, Mn doping effectively modified the lattice structure and surface characteristics of CZTS, indicating its potential to improve the material's performance in electronic devices, energy storage, and energy harvesting applications.