Low cost and large area novel chemical synthesis of Cu2ZnSnS4 (CZTS) thin films

Large area thin films of Cu2ZnSnS4 (CZTS) have been successfully deposited by a novel low cost chemical synthesis route. These CZTS films are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), electrical, wettability and optical absorption techniques. The XRD analyses revealed the formation of polycrystalline CZTS thin films with tetragonal crystal structure after annealing at 673 K. The scanning electron micrographs showed total substrate coverage with randomly distributed and diffused interlocked cubes. The optical band gap was estimated to be 1.5 eV. Wettability test revealed that as deposited and annealed CZTS films are hydrophilic with water contact angles 46° and 65°, respectively. The photoactivity of CZTS is tested by forming photoelectrochemical cell in polyiodide electrolyte.