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Abstract Heterogeneous photocatalysis is an emerging area of catalysis increasingly fraught with pains caused by the battle between hype and real‐ world application. Inspired by abundant yet diffuse solar energy and applications such as clean water and energy, ample motivation has provided the background for this situation. However, substantial fundamental (e. g., charge transfer, recombination), engineering (e. g., observed rates, photon management), and practical barriers (e. g., use of precious metals, competing technologies) have limited implementation. In this review, these are all outlined, in conjunction with typical strategies for improvements, with an emphasis on the use of semiconductor photocatalysts for the degradation of emerging forever chemical contaminants in water. The selected classes of forever chemical contaminants are (micro)‐plastics, per‐ and polyfluoroalkyl substances (PFAs), siloxanes, and dioxanes. Each has been identified as a key or emerging contaminant and often travel widely while accumulating in the atmosphere due to the lack of natural remediation processes. Recommendations to the field and opportunities for contributions are highlighted throughout and as part of the outlook to the future. 

Abstract In this study, high yields of CO are reported from CO₂using the silica (SiO₂) supported perovskite oxide, La_0.75Sr_0.25FeO₃(LSF), composites in the reverse water gas shift chemical looping (RWGS‐CL) process. XRD patterns of materials formed upon adding SBA‐15 to the perovskite sol‐gel precursor solution indicated successful formation of an orthorhombic perovskite oxide structure in the composites. The total surface area increased by ∼300 % with the addition of 50 % LSF to SBA‐15 by mass and surface accessibility of perovskite oxide crystallites was verified by CO₂chemisorption and XPS measurements. Composite materials achieved up to a factor of 10 increases in CO yields (∼3.5 vs 0.35 mmol CO/g_LSF) compared to pure LSF through six consecutive RWGS‐CL cycles at 700 °C. Following these RWGS‐CL cycles, XRD Scherrer analyses showed that the perovskite oxide in the composite material decreased in crystallite size. This approach to synthesis of supported perovskite oxides is expected to be valuable for large‐scale CO₂conversion by RWGS‐CL.