▎ 摘　　要

NOVELTY - Ultra-thin hydrotalcite-based composite photo-electrode comprises composite of two-dimensional nanosheet graphene and ultra-thin hydrotalcite growth on the surface of the bismuth vanadate electrode, the ultra-thin hydrotalcite has particle size of 3-5 mu m and sheet thickness of 3-4 nm. USE - The ultra-thin hydrotalcite-based composite photo-electrode is useful in photoelectric decomposition of water-coupled organic matter oxidation reaction (claimed). ADVANTAGE - The method: improves the oxidation efficiency of organic matter; and improves the overall energy efficiency and molecular reaction efficiency of the photoelectrolysis water reaction system. DETAILED DESCRIPTION - Ultra-thin hydrotalcite-based composite photo-electrode i.e. graphene- ultra-thin hydrotalcite/ bismuth vanadate (G-ULDHs/BiVO4) photoelectrode, comprises composite of two-dimensional nanosheet graphene and ultra-thin hydrotalcite growth on the surface of the bismuth vanadate electrode, the ultra-thin hydrotalcite has particle size of 3-5 mu m and sheet thickness of 3-4 nm. G = graphene; and U-LDHs = ultra-thin hydrotalcite of formula ((M2+1-xM3+x(OH)2)x+(An-)x/n.mH2O); M2+ = Ni2+, Co2+ and/or Zn2+; M3+ = Al3+ and/or Fe3+; An- = nitrate, sulfate and/or carbonate; n = 1 or 2; m = 5-15; and x = 1/3-1. INDEPENDENT CLAIMS are also included for: (1) preparing ultra-thin hydrotalcite-based composite photo-electrode, comprising placing the bismuth vanadate electrode into the mixed solution containing M2+, M3+, urea, ammonium fluoride, graphene and acetone and then carrying out hydrothermal reaction to obtain final product; and (2) photoelectric decomposition of water-coupled organic matter oxidation reaction comprises taking phosphate buffer solution as electrolyte in the closed series electrolytic cell adding organic substance or organic substance solution, mixing uniformly, discharging the nitrogen gas into mixed solution to clean the air, connecting an anode and cathode with power supply pair, at least one paired anodes and cathodes and a reference electrode forms a three-electrode system, isolating one of the cathodes from the other electrodes using proton membrane and the light is reacting under bias voltage of 0.6-1.6 V versus reversible hydrogen electrode (RHE) for 1-24 hours, allowing to stand for layer separation after completion of reaction and separating the upper organic phase product, where graphene- ultra-thin hydrotalcite/ bismuth vanadate photoelectrode is anode, platinum wire is cathode, silver/silver chloride is reference electrode. The direction of illumination is to illuminate the non-conductive surface of the anode.