The quaternary semiconductor Copper Zinc Tin Sulfide (CZTS) has attracted a lot of attention as a possible absorber material for solar cells due to its tunable bandgap (1 – 1.5 eV) and high absorption coefficient (>104 cm-1). However, the recombination of photogenerated carriers at defects and at interfaces of the layers in solar cell leads to poor performance of the device. In order to improve the optoelectronic device performance, it is necessary to understand more about the physical properties and the material aspects of the CZTS material. In this talk, I will be presenting the proposed work on nano-ink based CZTS thin films for photovoltaic applications.