Near-infrared Upconversion Nanomaterial-mediated Photothermal Conversion for Various Applications

In this chapter, we have systematically summarized the research advances on the synthesis and applications of near-infrared upconversion nanostructures. Therefore, a brief introduction to the concept and the synthesis method of upconversion nanoparticles (UCNPs) is given first. Then, we put our emphasis on the construction of composite nanostructures comprised of upconversion nanoparticles and semiconductors, polymers, or dyes; demonstrating the principles of energy harvesting to enhance the photothermal conversion efficiency. As a result, near-infrared upconversion nanomaterial-mediated photothermal treatment, including for cancer therapy and antibacterial therapy, can be carried out under weaker light illumination. Thus it forms guidance for the synthesis and design of near-infrared upconversion composite nanostructures, which is very easy to follow and comprehend.