Coconut shells are used for production of activated carbon. In this research, alkaline-bio scoured coconut shell powder was subjected to one step pyrolysis activation by using Phosphoric acid. The acid treated coconut shell particles were fed into a tube furnace with a heating rate of 10 oC min-1 until the temperature reached at 360 oC and dwell time 15 min in N2 atmosphere. Next, they were cooled in to room temperature. A thin film of n-Cu2O was fabricated by immersing a well cleaned copper sheet in a 10-3 M HCl solution for 60 h. CAC was placed on Cu/n-Cu2O substrate and ITO conductive glass plate was placed to fabricate Cu/n-Cu2O/CAC/ITO solid state photovoltaic cell. Here, CAC acts as an upper electrode, separate photo-generated charge carriers and enhance photocurrent. BET surface area analysis refuse reflectance spectra, photocurrent action spectra, time development of photocurrent and SEM morphology were used to analyze the prepared samples.