Thin film solar cell based on Cu₂ZnSnS₄ (CZTS) has the potential for large scale electricity production using solar radiation where the elements are earth abundant, inexpensive and environment friendly. The state of art CZTS solar cell has reached 12.6% efficiency while the commercial production will require at least 15% for economic feasibility. Here, we approach to understand the charge transfer dynamics in CZTS using ultrafast laser spectroscopy and focus on improving the efficiency of CZTS photovoltaics through the incorporation of a mesoscopic hole acceptor, nickel oxide. CZTS photo electrode is prepared using spray deposition of precursor solution, and characterized using SEM, TEM, XRD, XPS and Raman Spectroscopy. The performance of the material is tested in three electrode photo electrochemical cell.