Chiral Cu_2-xS quantum dots and their near-infrared photothermal conversion properties

Photothermal properties of semiconductor materials have been widely studied in recent years, while the chirality-related photothermal properties of semiconductor quantum dots remain unclear. In this work, the photothermal conversion properties of L/D-Cys-Cu_2-xS quantum dots under 808 nm-wavelength laser irradiation were studied. Our studies showed the photothermal conversion performance of D-Cys-Cu_2-xS quantum dots to be obviously better than that of L-Cys-Cu_2-xS quantum dots. They also showed the main copper component of the L-Cys-Cu_2-xS quantum dot to be Cu(II), and the content of Cu(I) in the D-Cys-Cu_2-xS quantum dot to be higher than that in the L-Cys-Cu_2-xS quantum dot. Raman measurements were taken to provide a meahanism for this photothermal conversion and indicated the involvement of local surface plasmon resonance (LSPR).