High-throughput Screening Study Of Photocatalytic Properties Of Metal Sulfide Composite GC 3 N 4

Compared with conventional physical, general chemistry, biological wastewater treatment technology, photocatalytic oxidation technology has many advantages, such as high removal efficiency, none secondary pollutant producing, mild reaction condition, easily operated and maintained, so has been gradually applied in wastewater treatment field. But the photocatalytic activity and solar energy utilization of most of photocatalytic materials ?e.g.,TiO₂? always were relatively low for the reason of their large photonic band gap and easily recombination of photo-generated electron hole pairs. There for it greatly limits the application of photocatalytic technology in the fields of environmental purification and development of new energy. Single component semiconductor catalytic materials exhibited a low photocatalytic activity, which was due to shorter absorption wavelengths and easily recombination of photo-generated electron hole pairs. Based on the above discussion, this paper will focus on the synthesis, characterization and photocatalytic performance of six kinds of metal sulfide?ZnS?CuS? Bi₂S₃?In₂S₃?Ce₂S₃?NiS? compound g-C₃N₄, which were formed a heterojunction compound catalytic material warehouse denoted as [M₂S_x]_N/g-C₃N₄ ?N=1-6 represent the six kinds of metal sulfide respectively?. Importantly, we screened out some catalytic material with high catalytic activity from [M₂S_x]_N/g-C₃N₄ using the high-throughput screening and calculate the composition ratio of each kind of metal sulfide, further proved in batch experiments. The main results are as follows:?1? Construction of reaction chips. First 4560 500×500 ?m hydrophobic react units were successfully constructed on the surface of glass slide ?size:75×25 mm2, thickness: 1 mm? using Ultraviolet Rays Glue ?UV glue? drop and coat-solidification method under UV irradiation. Second the g-C₃N₄ powder prepared by thermal condensation-agate beads shock were imported into react units using spraying method lead to the g-C₃N₄ capacity of each react unit was same, thus obtained substrate-1. Then the six kinds of metal solutions were printed to the g-C₃N₄ particles on the surface of substrate-1 using ink-jet printing technology, obtained substrate-2. At last, the six kinds of metal sulfide compound g-C₃N₄ were synthesized by steam bath vulcanization method on the surface of substrate-2. obtained the reaction chips.?2? Characterization. [M₂S_x]_N/g-C₃N₄ and g-C₃N₄ and were characterized by scanning electron microscopy ?SEM? and X-ray photoelectron spectroscopy ?XPS?, and results show that the prepared catalysts satisfied the experiment need.?3? The design of the reaction system of high-throughput screening. In order to meet the requirements such as high speed, high sensitivity, small sample size, precision of high-throughput screening used in this study, a set of suitable reaction system have been designed in this experiment. This system consists of micro reactor, fluorescence detection system and container, but black container is the running platform of the other two.?4?Photocatalytic performance tests and results of [M₂S_x]_N/g-C₃N₄. The photocatalytic performance of the prepared catalysts were evaluated by the degradation of eosin solution ?C0=1g/L? under UV-irradiation ??= 254,365nm? and blue visible light. The fluorescence intensity variation of eosin solution in the react units were record by camera at 8 time points during reaction. Compared with the fluorescence intensity images taken in the dark, blank experiment and degradation reaction, we believe that the dark spots appeared on the surface of reaction chip is due to eosin solutions was degraded by [M₂S_x]_N/g-C₃N₄.?5? The screening and metal sulfide composition ratio calculation of [M₂S_x]_N/g-C₃N₄ with higher with high catalytic activity.25 high catalytic activity and 3 low catalytic activity react units were screened out by image analysis, then metal sulfide composition ratios were calculated and further proved in batch experiments. At the same time the experiment results indicated that the feasibility, correctness and scientific of high throughput screening used in this study.