This book accounts for the necessary introduction to PEC solar cells. Different types of solar cells have been explained and discussed under their classified heads. The advantages and disadvantages of PEC solar cells over the solid-state photovoltaic cells have also been discussed. "Photoelectrochemical studies of MX2 crystals (Part 2)" deals with the experimental work of Photoelectrochemical cell using TMDC crystals. It also describes author's attempt to fabricate PEC solar cells using MX2 crystals. Various solar cell parameters have been measured e.g. short circuit current, open circuit voltage, fill factor, efficiency, dark current and dark voltage etc. for semiconductor electrodes prepared using MX2 crystals. It also shows semiconductor electrolyte interface characterized by locating valence and conduction band edges, for which flat band potential measurements were carried out by using Mott - Schottky plots. These studies justify the selection of appropriate electrolyte for PEC work.