Experimental investigation of a unique solar photoelectrochemical hydrogen generating reactor for clean fuels

•The novel electrode design is proposed.•The reactor design collects maximum sunlight and produces highest hydrogen rate.•The hydrogen production efficiencies are studied for various operating conditions.•The hydrogen yield rate is evaluated for vertical and tilted light conditions.•The enhancement by tilted light can reach 80% of the enhancement by vertical light. A new photoanode configuration utilizes the maximum light over daytime at any angle of the delivered rays due to its meshy dome design. This specific dome design of the photoanode is unique and helps increase the illumination electrode area, and the mesh type of configuration makes the rays reach inside the dome body better to increase the received sunlight at any angle of the solar rays. The mesh dome photoanode is manufactured of stainless steel and coated with titanium dioxide sol–gel solution using the dip-coating method. This photoanode is immersed in 0.1 M potassium dioxide solution with titanium mesh dome cathode and examined under the solar simulator at vertical light and 45° tilted light conditions. The present experimental measurements indicate that the highest hydrogen mass generation rate produced under the vertical light condition is 5.58 µg/s occuring at the photocurrent density of 1.62 mA/cm2. Moreover, the exergy and energy efficiencies that could be achieved at the vertical light condition are 0.81% and 1.17%, respectively. The enhancement of the hydrogen mass production rates that happens at tilted light conditions is varied between 75% and 80% of the enhancement by vertical light conditions. According to the experimental results, this photoanode design is effective during the daytime considering the angle of sun rays.