Tailoring Oxygen Carriers through Doping for Next-Generation Chemical Looping Technologies: Review and Perspectives

Modulating anionic oxygen in metal oxides through doping offers transformative potential for enhancing oxygen carriers in chemical looping processes by improving the redox performance and addressing challenges such as sintering and carbon deposition at high temperatures. Doping introduces oxygen vacancies and lattice strain, enhancing the oxygen mobility for the selective oxidation of fuels into desired products. The performance of oxygen carriers is critically influenced by the dopant type, concentration, and distribution; excessive doping leads to agglomeration and structural degradation, while insufficient doping results in suboptimal reactivity. Co-doping and doping in supports provide synergistic benefits, improving the oxygen transport, stability, and selectivity. This review explores the impact of dopant concentration, codoping, and support doping on oxygen carrier performance, emphasizing the need for optimal doping strategies to balance structural integrity and redox efficiency. It highlights advancements and case studies demonstrating selective fuel oxidation, offering insights into optimizing the oxygen carrier design for sustainable energy applications.