Figure 5.

(a) Illustrates grain boundary maps of polycrystalline CZTSSe under varying mechanical stress—namely flat, concavely bent, and convexly bent configurations. Electrons are depicted as red spheres while holes are blue. With a bending radius set at 50 mm and a maximum flexure event count of 1000, (b,c) delineates the variation rate in photovoltaic device parameters during concave and convex bending, respectively, while (d,e) quantify the change rate in series and parallel resistances under identical bending conditions, corresponding to concave and convex deformation. (Reprinted with permission from Ref. [56]. Copyright 2022, Springer Nature).