▎ 摘 要
NOVELTY - A rod-shaped cerium-doped zinc oxide and graphene composite photocatalyst comprises commercial graphene oxide, cerium nitrate hexahydrate, ammonia and sodium hydroxide as alkali source, zinc nitrate hexahydrate, and deionized water and absolute ethanol as detergent. The photocatalyst is prepared by adding zinc nitrate hexahydrate to a beaker containing deionized water, stirring, dropping ammonia water to adjust pH, stirring to obtain solution A, adding to sealed PTFE-lined stainless steel autoclave, reacting, washing with deionized water and absolute ethanol, centrifuging, and vacuum drying to obtain zinc oxide sample; repeating preparation of solution A; and adding graphene oxide to beaker containing deionized water, stirring, dropping sodium hydroxide solution to adjust pH, stirring to obtain solution B, mixing solutions A and B, stirring, transferring to sealed PTFE-lined stainless steel autoclave, reacting, washing with deionized water and absolute ethanol, and vacuum drying. USE - Rod-shaped cerium-doped zinc oxide and graphene composite photocatalyst. ADVANTAGE - The method is simple and has low cost. The photocatalyst has high catalytic efficiency, high yield, and no pollution. DETAILED DESCRIPTION - A rod-shaped cerium-doped zinc oxide and graphene composite photocatalyst comprises commercial graphene oxide, zinc nitrate hexahydrate, cerium nitrate hexahydrate, ammonia and sodium hydroxide as alkali source, and deionized water and absolute ethanol as detergent. All raw materials are analytically pure without further purification treatment. The photocatalyst has excellent photocatalytic performance under visible light irradiation. The photocatalyst is prepared by: (A) adding 0.524 g zinc nitrate hexahydrate to a beaker containing 25 mL deionized water, stirring for 30 minutes, dropping ammonia water to adjust pH to 11, stirring for 1 hour to obtain solution A, adding to sealed PTFE-lined stainless steel autoclave, reacting to 180 degrees C for 10 hours, washing repeatedly with deionized water and absolute ethanol, centrifuging to obtain white product, and vacuum drying to 70 degrees C for 10 hours to obtain zinc oxide sample; (B) repeating preparation of solution A; adding 0.1125 g graphene oxide to beaker containing 25 mL deionized water, stirring for 30 minutes, dropping sodium hydroxide solution to adjust pH to 4, stirring for 1 hour to obtain solution B, mixing stirred solution A and B, stirring for 30 minutes, transferring to sealed PTFE-lined stainless steel autoclave, reacting to 180 degrees C for 10 hours, washing with deionized water and absolute ethanol repeatedly, and vacuum drying to 70 degrees C for 10 hours to obtain ZG sample; (C) adding 0.524 g zinc nitrate hexahydrate to a beaker containing 25 mL deionized water, adding 0.0059 g (1 wt.%) cerium nitrate hexahydrate, stirring for 30 minutes, adding sodium hydroxide to adjust pH to 11, stirring for 30 minutes, dropping ammonia water, and stirring for 1 hour to obtain solution C; (D) adding 0.1125 g graphene oxide to a beaker containing 25 mL deionized water, ultrasonicating for 30 minutes, dropping sodium hydroxide to adjust pH to 4, stirring for 1 hour to obtain solution D, mixing solution C and solution D, stirring for 30 minutes, transferring to sealed PTFE-lined stainless steel autoclave, reacting to 180 degrees C for 10 hours, washing with deionized water and absolute ethanol repeatedly, and vacuum drying to 70 degrees C for 10 hours to obtain ZGCeO1 sample; (E) preparing 2 wt.% ZGCeO2, 3 wt.% ZGCeO3 and 4 wt.% ZGCeO4 samples using the same experimental method used in ZGCeO1 sample; (F) subjecting obtained 6 samples to characterization methods such as X-ray diffraction, scanning electron microscope, element mapping, UV-visible light absorption spectrum and fluorescence excitation spectroscopy to analyze the morphology, structure, composition and optical properties, and performing photocatalytic performance test using 350 W xenon lamp as light source and 10 mg/L methylene blue (MB) as target dye for degradation; and (G) adding 30 mg samples into four test tubes containing 50 mL organic dyes, stirring, subjecting to dark treatment for 30 minutes until organic dye and photocatalyst reach the equilibrium of adsorption and desorption, turning on xenon lamp, taking out 3-4 mL solution every 30 minutes, measuring absorption peak of MB at 664 nm by UV-visible spectroscopy, calculating degradation rate, evaluating photocatalytic performance of the sample with the change of absorbance of MB solution. According to the photocatalytic results, it was found that the 2 wt.% ZGCeO2 sample showed the highest photocatalytic activity.