To grind or not to grind? The influence of mechanical and thermal treatments on the Cu/Zn disorder in Cu2ZnSn(SxSe1-x)4 monograins

Kesterite-type based thin film solar cell technologies are mainly on polycrystalline absorber layers. A promising low cost alternative technology uses Cu2ZnSn(SxSe1-x)4 (CZTSSe) monograins (single crystals of 20–100 μm size) which fixed in a polymer matrix to form flexible cell. The Cu/Zn disorder is discussed as possible reason for band tailing causing voltage losses limiting the efficiency CZTSSe-based devices. experimental determination order parameter Q quantitative measure disorder, requires differentiation between isoelectronic cations Cu+ and Zn2+. An in-depth analysis neutron diffraction data allows type concentration intrinsic point defects including distinction Cu Zn. Neutron large sample volumes, thus offer unique possibility correlate structural CZTSSe with device performance parameters. In this study we tackle influence grinding stoichiometry deviations, well optoelectronic properties monograins. Moreover, an easy methodology Raman scattering spectroscopy proposed assessment compounds.