Uv 2600 system

XRD patterns were supplied by Bruker D8 Advance. TEM image and EDS images were captured by Tecnai G2 F20 with EDS Inca X–Max (Oxford). Scanning electron microscopy (SEM) images were given by Gemini SEM 300. In-situ XPS measurement was operated on a Kratos-Axis Ultra DLD instrument using a xenon lamp as the light source. The binding energy of C1s at 284.8 eV was used for energy calibration. VB XPS spectra and UPS of the samples were collected by Escalab Xi+ (Thermo Scientific), and UV–vis DRS was determined by the UV-2600 system (Shimadzu). The content of K and Li was obtained from ICP-OES (PE Avio 200) and the content of H was obtained from O, N, and H co-meter (LECO ONH836). AFM images and KPFM images were captured by Bruker MultiMode 8, and the probe used was a silicon probe. During the measurement, a xenon lamp was used as the light source, and the light irradiation time was 15 min. In this case, the powder sample was dispersed in an ethanol solution and then dropped onto the silicon wafer to form a uniform film for testing.
In-situ DRIFTS characterization was operated on a Nicolet iS50 FTIR spectrometer. ¹³C isotope tracing experiment was performed by mass spectrometry (Finnigan MAT 271). The O₂ generated during the CO₂ photoreduction process was detected by a gas chromatograph (GC14C, Shimadzu) with a TCD detector.