A comprehensive review: Functional nanomaterials for renewable energy: Innovations, applications, and sustainable strategies

Enhancing the effectiveness and functionality of renewable energy sources remains a top concern. Therefore, nanotechnology has been explored as a possible means of improving various renewable energy systems, as it makes energy generation, storage, and conversion more efficient at the nanoscale. Nanomaterials like carbon nanotubes, metal nanoparticles, graphene, and metal oxides can significantly improve the efficiency of solar cells, fuel cells, and other renewable technologies. While lowering weight, graphene and carbon nanotubes enhance the electrical conductivity and durability of battery electrodes. Fuel cells and solar hydrogen generation systems benefit from the enhanced charge transfer and reaction kinetics provided by nanostructured metal oxides such as TiO₂ and CeO₂. The high surface area and optical absorption properties of nanomaterials enable more efficient sunlight harvesting in solar cells, as nanoparticle coatings on solar cell surfaces improve light trapping and anti-reflection capabilities. Nanotechnology also enables advanced energy storage through improved batteries, supercapacitors, and hydrogen storage systems. Batteries with nanoparticle-enhanced electrodes exhibit higher power density and faster charging capabilities compared to conventional batteries. Supercapacitors fabricated with nanomaterials demonstrate high capacitance and cycling stability. The objective of this research is to investigate the ability of nanotechnology to enhance the performance and efficiency of renewable energy systems. Through comprehensive analysis of existing studies, new developments and key applications requiring further research are identified. Nanotechnology presents immense potential for advancing renewable energy technologies through the unique properties of nanomaterials. By improving things like electrical conductivity, surface area, catalytic activity, and optical absorption at the tiny nanoscale, we can greatly boost how we generate, store, and use energy. However, more research is needed to fully harness the capabilities of nanotechnology, including improved nanomaterial synthesis and device fabrication methods. Overcoming challenges in scale-up and commercialization will be critical for translating laboratory successes into commercially viable renewable energy systems. This research will provide great benefits to those who intend to use renewable energy storage, whether they manufacture products and use these products to generate and store energy or regulate the use of renewable energy. • Nanomaterials boost renewable energy efficiency & storage. • Graphene & CNTs enhance conductivity in batteries & solar cells. • Nanoparticles optimize light absorption for solar energy. • Nanotech enables fast-charging batteries & high-capacity storage. • Scale-up challenges must be solved for real-world impact.