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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. 

Artificial nano‐ and microswimmers are promising as versatile nanorobots for applications in biomedicine, environmental chemistry, and materials science. Herein, a hybrid micromotor containing a conjugated polymer (poly(3,4‐ethylenedioxythiophene) (PEDOT), and a catalytic structure composed of platinum (Pt) synthesized using a template‐supported electrochemical deposition process is reported. The movement of this PEDOT/Pt micromotor is characterized under chemical power generated by hydrogen peroxide catalysis, and acoustic power generated by surface acoustic waves (SAWs). The acoustic radiation force acting between the bubbles, the secondary Bjerknes force, is shown to increase the micromotor speed. The movement of the micromotor is precisely controllable using the acoustic field, providing excellent response time and reproducibility over a wide dynamic range. A theoretical model is developed to understand and predict the micromotor propulsion under the hybrid chemical and acoustic power. Predicted micromotor speeds are in excellent agreement with experiment as a function of peroxide fuel concentration, SAW field strength, and SAW frequency. The model allows for design of micromotor geometries and acoustic field strengths to achieve desired speed with excellent on/off control.