Conducting polymeric nanocomposites: A review in solar fuel applications

Over the last few decades, research is being carried out in the field of photocatalysis to investigate for fuels production in sustainable manner. Due to an energy depletion and CO₂ emission in the current situation urge us to produce alternative fuels. Water splitting and the reduction of carbon dioxide using various photocatalysts are being developed as promising sustainable methods to obtain eco-friendly energy sources. Conducting polymers (CP) stand out among the current pool of studied photocatalysts due to their high light absorption efficiency, good stability, tunable electronic characteristics, and cost effectiveness. Various CP, such as polyaniline, polythiophene, and polypyrrole have been integrated with different semiconducting nanomaterials to produce photocatalytic composites. Therefore, in this review, we focus on the synthesis of CP and their nanocomposites for application in CO₂ photoreduction and water splitting into fuel production using different polymeric composites. Many composite photocatalysts show synergistic effects between the polymeric material and other counterparts in the composite. The improvement in the inactivity of the composite can be attributed to the band configurations of the composite. Improving the separation of excitons, widening the light absorption region, enhancing the substrate adsorption, and preventing photocorrosion conductive polymers can significantly increase the photocatalytic activity under visible light. The addition of conducting polymers with an inorganic materials dramatically change their band positions and may reduce the possiblilty of electron hole recombination. Here, we explain by what means conductive polymeric material can improve the efficiency of the composite in an organized manner, thereby providing a comprehensive reference to the field. Finally, the current challenges and future perspectives of polymeric catalysts have been discussed briefly.