Xplora laser raman spectrometer

Transmission electron microscope (TEM) images were taken on a transmission electron microscope (Tecnai G2 20 TWIN, FEI, USA) operated at an acceleration of 10 kV by dropping solution onto a carbon-coated copper grid. Dynamic light scattering (DLS) and zeta potential were measured at 25°C on a Zetasizer Nano ZS90 analyzer (Malvern Instrument Ltd, UK). Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) methods were used to test the surface area, the pore size distribution, and the pore volume. Fourier transform infrared (FT-IR) spectra were conducted on Thermofisher Nicolet 6700 fourier transform infrared spectrometer with KBr pellets. Raman spectra were performed on XploRA laser Raman spectrometer (HORIBA JobinYvon, France) with excitation of 532 nm. Confocal laser scanning microscopy (CLSM) images were performed on Nikon C2+ laser scanning confocal microscope (Nikon, Japan). Photothermal effect was tested on an 808 nm consecutive NIR laser with spot size of 5 mm×6 mm (Changchun New Industries Optoelectronics Technology Ltd., People’s Republic of China). Thermal images were taken on an infrared camera thermographic system (Infra Tec, VarioCAM research)

Raman spectroscopy was performed on an XploRA laser Raman spectrometer (HORIBA, France). The samples were prepared in the same process as that for ¹³C CP-MAS NMR experiments. The Raman spectra were obtained with grating of 1200, excitation wavelength of 785 nm, laser power of 90 mW, 10 s accumulation and 10 times scan.