Multi‐Channel Optical Device for Solar‐Driven Bacterial Inactivation under Real‐Time Temperature Feedback.

Solar‐driven photothermal antibacterial devices have attracted a lot of interest due to the fact that solar energy is one of the cleanest sources of energy in the world. However, conventional materials have a narrow absorbance band, resulting in deficient solar harvesting. In addition, lack of knowledge on temperature change in these devices during the photothermal process has also led to a waste of energy. Here, we presented an elegant multi‐channel optical device with a multilayer structure to simultaneously address the above‐mentioned issues in solar‐driven antibacterial devices. In the photothermal channel, semiconductor IrO2‐nanoaggregates exhibited higher solar absorbance and photothermal conversion efficiency compared with nanoparticles. In the luminescence channel, thermal‐sensitive Er‐doped upconversion nanoparticles were utilized to reflect the microscale temperature in real‐time. The bacteria were successfully inactivated during the photothermal effect under solar irradiation with temperature monitoring. This study could provide valuable insight for the development of smart photothermal devices for solar‐driven photothermal bacterial inactivation in the future. [ABSTRACT FROM AUTHOR]