Exploratory insight into the contribution of chemical components of photo galvanic electrolyte towards potential, power and current of photo galvanic cells

Abstract

Photo-galvanic cells are based on the diffusion of ions in the electrolyte (a mixture of sensitizer, reductant, alkali, surfactant, and solvent). The photogalvanics is characterized by the abrupt jump in the photo-potential during charging of the cell. Photo-galvanic cells have been widely studied using the complete electrolyte. The migration of current by ions gives impression that any of the ionic species individually (like sensitizer/reductant/etc.) may show current, potential, and photogalvanics. This aspect of photogalvanics of individual chemical components is missing in the literature. Therefore, the photogalvanics of the individual chemicals, mixtures of the chemicals, and complete electrolyte have been studied in present research to have insight into (i) the genesis of the current and potential generated from the cell in non-illuminated state (dark conditions), and (ii) the necessary chemical conditions required for the photogalvanics.The average open-circuit potential (Voc) and short-circuit current (Isc) in dark conditions for water, Lactic acid reductant, Cocamidopropyl betaine surfactant, Carmoisine-A dye, NaOH alkali, complete electrolyte (at low pH), and complete electrolyte (at very high pH) is 286 mV, 4 µA; 214 mV, 3 µA; 278 mV, 4 µA; 268 mV, 9 µA; 295 mV, 8 µA; 278 mV, 8 µA; and 463 mV, 253 µA, respectively. The average Voc and Isc from illuminated water, Lactic acid reductant, Cocamidopropyl betaine surfactant, Carmoisine-A dye, NaOH alkali, complete electrolyte (at low pH), and complete electrolyte (at very high pH) is 296 mV, 3 µA; 182 mV, 4 µA; 218 mV, 4 µA; 135 mV, 3 µA; 275 mV, 9 µA; 167 mV, 6 µA; and 731 mV, 2500 µA, respectively. Thus, no photogalvanics has been observed for individual chemical components, and mixtures of two or more chemical components of the electrolyte. The photogalvanics is observed only for complete electrolyte at high pH.