Kesterite based thin film absorber layers from ball milled precursors

Abstract

The existing thin film technology involves rare earth and toxic materials. Cu 2 ZnSnS 4 , its selenide and sulfo selenide analogues have acquired as the most promising alternate absorber material group in thin film technology due to the abundance and non toxic constituent elements. We present a facile, green and low cost method for synthesis of CZTS/(Se) films. Precursor powders using Cu, Zn, Sn, S and Se, was prepared by ball milling. Starting with ball milled metallic precursor powders we synthesized kieserite thin films by doctor blade coating process and subsequent annealing. Doctor blade coating method is one of the cheapest non toxic non vacuum based chemical deposition processes. A comparative study of ball milled powder and films prepared from the precursors has been presented and interesting aspects of structure, morphology and composition were explored after ball milling, and films formed after annealing. Chalcogens (S or Se) plays an important role in the construction of tetragonal phase. A combined TGA-DSC, X-ray diffraction, Raman, TEM, EDX and UV-Vis-NIR study showed marked change in film property after annealing.

Photovoltaic materials: Cu2ZnSnS4 (CZTS) nanocrystals synthesized via industrially scalable, green, one‐step mechanochemical process

“…Various precursors were applied-either elements or compounds. As for milling, dry mode 12,13,15,[18][19][20][21][22][23][24][25][26] and wet mode 14,16,17,27 were applied. However, the wet mode was not primarily used for synthesis but rather to improve the homogeneity of already-prepared CZTS applied for subsequent thin film formation.…”