CeO2-based catalysts for photocatalytic degradation of volatile organic compounds: A comprehensive review

  • 0School of Energy & Environment, City University of Hong Kong, Hong Kong, China. Electronic address: u3005831@connect.hku.hk.
Journal of environmental management +

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Abstract

Volatile organic compounds (VOCs) are hazardous air pollutants that pose significant risks to human health, highlighting the need for efficient and sustainable removal technologies. While titanium dioxide (TiO2) has long been the dominant photocatalyst for VOCs degradation, cerium dioxide (CeO2) has emerged as a promising alternative due to its unique Ce3+/Ce4+ redox behavior and abundant oxygen vacancies. However, its photocatalytic efficiency is often limited by poor light absorption and rapid charge recombination. This review systematically summarizes recent advances in the design and modification of CeO2-based catalysts for VOCs degradation, including morphology modification, metal and non-metal doping, defect engineering, and heterostructure construction. It also identifies key factors affecting degradation efficiency, such as relative humidity, types of VOCs, concentration of VOCs, airflow rate, and light source. Furthermore, the review discusses emerging strategies to enhance catalyst performance. By integrating materials design with an analysis of these key factors, this review provides a comprehensive and forward-looking perspective on the development of advanced CeO2-based photocatalysts for VOCs removal.

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