The optical characteristics of C@Cu core-shell nanorods for solar thermal applications

The development of high-efficiency, low-cost and pollution-free new energy has become the focus of scientific research in the 21st century. As for this aspect, exploring more efficient nanoparticles (NPs) for direct absorption solar collectors (DASCs) has become a key issue in solar collector applications. However, the common NPs are usually composed of precious metal gold (Au) or silver (Ag). In this work, we propose a core-shell nanorod surrounded by a Cu shell with a C core and study its absorption properties in solar absorption spectroscopy. The aim is to explore its capability in DASC solar absorption efficiency. The research results show that this nanorod can reduce the application cost while maintaining high solar absorption efficiency. And the possible effects of nanoparticle shell defects during nanoparticle synthesis are considered. The results are as expected, which significantly impacts solar energy absorption. In addition, the C@Cu core-shell nanorods have a wider absorption band and higher resonance absorption peak compared with single Cu NPs. The results indicate that the core-shell composite nanorods proposed in this work have great potential in the application of DASC and are expected to be one of the candidate materials.