Emerging trends in photocatalytic energy and environmental applications of CuBi₂O₄: A review of improvement strategies

Rapid industrialization has exacerbated environmental pollution and energy crises, necessitating the development of sustainable technologies for environmental remediation and clean energy generation. Among various solar-driven approaches, semiconductor assisted photocatalysis has emerged as a green and efficient method for pollutant degradation and energy production. CuBi₂O₄, a p-type semiconductor with a spinel structure and a narrow bandgap (approximately 1.5–1.8 eV), has shown great potential due to its strong visible light absorption, abundance, and low toxicity. However, its photocatalytic performance is hindered by rapid charge carrier recombination and limited oxidation reduction capabilities. This review systematically explores the structural and electronic properties of CuBi₂O₄, along with various fabrication methods. Furthermore, recent advancements in performance enhancement strategies including elemental doping and heterojunction engineering are critically analysed, with an emphasis on how these modifications influence carrier dynamics, light harvesting, and surface reactivity. Overall, this review offers a comprehensive perspective on the rational design of CuBi₂O₄ based photocatalysts for efficient solar energy utilization, aiming to guide future innovations in energy and environmental applications.