Nano-inks are conductive NPs (NPs) that absorb incoming light to produce excited electrons and create energy. The nano-inks for PV (PV) applications are still an exploratory field, and many challenges remain in designing more efficient nano-ink PV systems. Current researches on this topic tend to focus on achieving stable and reliable PV systems using economic formulations of nano-inks. This chapter theme addresses PV performance optimization through nano-ink applications. The survey will be focusing on the methods of preparations, characterization, and the best-achieved results of these different formulations from nano-ink systems. However, the advantages and disadvantages plus the future prospects of these nano-inks PV systems will be discoursed. Consequently, this chapter aims to provide an overview of the different systems used as nano-inks, methods of synthesis, and applications in PV systems besides debating their efficiency, toxicity, and economic value. In addition, the conclusion estimates the maximum power-conversion efficiency for all types of the introduced nano-ink solar cells and presents approaches for achieving its future prospective.