Semiconductor Electrodes: XVIII . Liquid Junction Photovoltaic Cells Based on Electrodes and Acetonitrile Solutions

Abstract

Regenerative photoelectrochemical cells (PEC) were constructed utilizing single crystal in acetonitrile solutions. Solution redox couples (anthraquinone, p‐benzoquinone, dimethyl ferrocene, ferrocene, hydroxymethyl ferrocene, and tetramethyl‐p‐phenylenediamine) whose standard redox potential varied by over 1.2V, were photooxidized at the semiconductor electrode and reduced at a Pt counterelectrode converting light directly into electrical energy. A power conversion efficiency of 14% was observed for the electrode in a ferrocene‐ferricenium acetonitrile solution at a radiant intensity of 0.52 mW/cm2 of 720–800 nm light. The efficiency and stability were found to be very dependent upon the residual water concentration, radiant power, and concentration of electroactive species.