Photoelectrode Fabrication and Modular PEC Reactor Integration for Stable Solar Hydrogen Production
Ingrid Rodríguez‐Gutiérrez, Lizandra R. P. Peregrino, Gabriel H. Morais, Francine Côa, Diego Stéfani T. Martinez, Renato V. Gonçalves, Flávio L. Souza
Abstract
High Resolution Image Download MS PowerPoint Slide Photoelectrochemical (PEC) water splitting is a promising route for solar hydrogen production, yet scalability and environmental safety remain key challenges. Here, we present a modular PEC platform using hematite photoelectrodes fabricated via a scalable polymeric precursor method with uniform Al/Zr comodification to enhance charge transport and adhesion. A total of 100 reproducible photoelectrodes were produced and characterized using customized PEC cells with two different active areas (0.28 and 1 cm 2 ) to assess scale-dependent performance. Ten photoelectrodes were integrated into each 3D-printed reactor, demonstrating an effective small-scale assembly. Ten such reactors could form a 100 cm 2 module, supporting scalable deployment. Each reactor delivered stable photocurrents (∼10 mA at 1.23 V RHE ) for over 120 h under 1 sun. Outdoor operation of two series-connected reactors reached 20 mA. Ion leaching remained below national discharge limits, confirming environmental safety. This work establishes a scalable, stable, and modular PEC strategy, advancing hematite-based devices toward real-world solar hydrogen production.