2.3 Photocatalytic evaluation
In a 63 mL sealed quartz bottle, 0.01 g catalyst was dissolved in 30 mL Na2S/Na2SO3 (0.35 M/0.25 M). N2 was used replace the oxygen in the bottle, the exhaust process takes about 5 min. Then the treated quartz bottle was put into a nine-channel photocatalytic reaction system (PCX50A Discover) for hydrogen evolution experiment. Under the illumination of 5W LED white light, extract 0.5ml of gas from the bottle every hour and injected it into the Tianmei GC7900 gas chromatograph (TCD, 13Xcolumn) with N2 as carrier gas, the hydrogen content in the gas is identified and recorded. Moreover, the apparent quantum efficiency (AQE) of the MCNS-10 was measured under a 300 W xenon lamp. The light source was transmitted through filters with specifications of 400, 420, 450, 475, 500, 520, 550 and 600 nm, respectively. The number of incident photons fluxes was tested using a power meter (PL-MW200 radiometer). The calculation formula for AQE was as follows at different wavelengths.