Green ammonia production has been an important topic that is being researched during the last decades due to the increasing demand and to cut down CO2 emissions. One of the promising pathways to achieve green chemical energy synthesis is the Photoelectrochemical (PEC) approach. To realize low-cost and scalable green ammonia production, the direct integration of solar photovoltaic modules and catalysts as a Photovoltaic-Electrochemical (PV-EC) system is highly suitable. In this study, Molybdenum Carbide(Mo2C) decorated with different metal nanoparticles (Pt, Pd, Ru) is being investigated as a potential nitrate reduction (NO3RR) to ammonia. Here various metal-decorated M o2C was successfully synthesized by the chemical reduction method. The metal-decorated M o2C is characterized by Transmission Electron Microscopy(TEM), Raman Spectroscopy, and X-ray diffraction(XRD) analysis and confirmed the formation. Initially, electrocatalytic NO3RR was carried out, and Pt decorated Mo2C was found to demonstrate high Faradic efficiency and NH3 of 30% and 4400 μg/h/cm2. Next, PV-EC was carried out, and a stable solar-powered NO3RR was carried out with Pt-M o2C and Si PV module. The proposed system delivers a yield of 600 ug/h/cm2 and a Faradic Efficiency of 7% .