Facile Synthesis of BaCeO3@g-C3N4 n-type Semiconductor Heterojunctions for Green Hydrogen Production via Multimodal Photo and Electro-catalytic Pathways

Abstract

Development of an efficient and stable catalytic system for the production of sustainable hydrogen has remained a pivotal challenge in photocatalysis and electrocatalysis. In this work, we have reported a facile calcination strategy for synthesizing n-type BaCeO3@g-C3N4 heterojunctions that synergistically integrate the strong visible-light response of g-C3N4 with the high ionic conductivity and redox versatility of BaCeO3 perovskite. The BaCeO3@g-C3N4 heterojunction formation was confirmed through XRD, SEM, HR-TEM, and XPS techniques. The BaCeO3 nanoparticles were found to be evenly anchored on g-C3N4 nanosheets post-calcination as compared to non-calcined BaCeO3@g-C3N4. As-prepared heterostructures exhibited remarkable activity under different water-splitting conditions. The optimized 20% BaCeO3@g-C3N4 demonstrated enhanced photochemical (PC) H2 production performance (15.21 mmol/gcat/h) compared to pristine g-C3N4 and BaCeO3. Electrochemical (EC) and photoelectrochemical (PEC) investigations also corroborated its advanced HER activity at low overpotentials. The superior H2 evolution activity is attributed to the optimized band alignment and the interfacial charge transfer between g-C3N4 and BaCeO3. This work presents a multimodal H2 production activity of BaCeO3@g-C3N4 heterojunctions via photochemical and photo-/electrochemical methods.