fig3
Figure 3. (A) XRD patterns of ZIS, VZn-ZIS, UCNPs, and UCNPs@VZn-ZIS; (B) DRS of VZn-ZIS, UCNPs, and UCNPs@VZn-ZIS; XPS spectra of Zn 2p, In 3d and S 2p of VZn-ZIS and UCNPs@VZn-ZIS (C-E); (F) EPR signals of ZIS and VZn-ZIS. XRD: X-ray diffraction; ZIS: ZnIn2S4; VZn-ZIS: Zn vacancy-rich ZnIn2S4; UCNPs: up-conversion nanoparticles; DRS: diffuse reflectance spectra; XPS: X-ray photoelectron spectroscopy; EPR: electron paramagnetic resonance.
