ZIF-8 metal–organic frameworks and their hybrid materials: emerging photocatalysts for energy and environmental applications

In the face of escalating environmental challenges such as fossil fuel dependence and water pollution, innovative solutions are essential for sustainable development. In this regard, zeolitic imidazolate frameworks (ZIFs), specifically ZIF-8, act as promising photocatalysts for environmental remediation and renewable energy applications. ZIF-8, a subclass of metal–organic frameworks (MOFs), is renowned for its large specific surface area, high porosity, rapid electron transfer ability, abundant functionalities, ease of designing, controllable properties, and remarkable chemical and thermal stability. However, its application as a standalone photocatalyst is limited by issues such as particle aggregation, poor water stability, and insufficient visible light absorption. By integrating ZIF-8 with various photoactive materials to form composite catalysts, these drawbacks can be mitigated, leading to enhanced photocatalytic efficiency. The review discusses the synthesis, properties, and applications of ZIF-8-based photocatalysts in light-driven H₂ evolution, H₂O₂ evolution, CO₂ reduction, and dye and drug degradation. It also highlights the challenges and future research directions in developing cost-effective, scalable, and environmentally friendly ZIF-8 composites for industrial applications. The potential of ZIF-8 composites to contribute to sustainable global energy solutions and environmental cleanup is significant, yet further exploration is required to harness their capabilities thoroughly.