Fotoelectrólisis del agua usando celdas solares de perovskita inorgánica CsPbBr₃ como fuente de electricidad y la aleación de alta entropía FeNiCoCuMo como electrocatalizador de la reacción de evolución de oxígeno

The search for sustainable energy sources drives the development of efficient systems for water electrolysis, with the Oxygen Evolution Reaction (OER) being the main kinetic bottleneck. This study presents the design, characterization, and evaluation of a novel experimental setup intended to catalyze the OER in a robust and cost-effective manner. The system integrates two main components: a “triple stack” CsPbBr₃ inorganic perovskite solar cell array as the electric power source, and a FeNiCoCuMo high-entropy alloy as a high-performance electrocatalyst in an alkaline medium. Photovoltaic characterization yielded remarkable open-circuit voltage (Voc) values exceeding 1.45 [V] and current densities between 3 and 4 [mA/cm²]. Electrochemical analysis of the alloy revealed favorable kinetics for the OER, achieving overpotentials (η₁₀) of 285[ mV] at 10[ mA/cm²], in addition to a Tafel slope of 59 [mV/ dec] and an exchange current density (j₀) of 1 × 10⁻³ [A/cm²], values that rival or surpass commercial noble-metal catalysts. Upon integrating both components, the system demonstrated a maximum Faradaic efficiency of 73.08 % under constant and stable operating conditions over a period of 6 h, validating a promising approach. The results confirm the feasibility of using stable inorganic perovskites and high-entropy alloys for the development of energy-demanding chemical reactions such as the OER, thereby contributing to research in clean energy technologies.