Heteropolyacids-Immobilized Graphitic Carbon Nitride:Highly Efficient Photo-Oxidation of Benzyl Alcohol in the Aqueous Phase  

作　　者：Lifu Wu Sai An Yu-Fei Song 

机构地区：[1]State Key Laboratory of Chemical Resource Engineering,Beijing Advanced Innovation Center for Soft Matter Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China

出　　处：《Engineering》2021年第1期94-102,共9页工程（英文）

基　　金：This research was supported by the National Nature Science Foundation of China(21625101,21521005,and 21808011);the National Key Research and Development Program of China(2017YFB0307303);Beijing Natural Science Foundation(2202039);the Fundamental Research Funds for the Central Universities(XK1802-6,XK1902,and 12060093063).

摘　　要：Benzaldehyde is a highly desirable chemical due to its extensive application in medicine,chemical synthesis and food sector among others.However,its production generally involves hazardous solvents such as trifluorotoluene or acetonitrile,and its conversion,especially selectivity in the aqueous phase,is still not up to expectations.Hence,developing an environmentally benign,synthetic process for benzaldehyde production is of paramount importance.Herein,we report the preparation of a photocatalyst(PW_(12)-P-UCNS,where PW_(12)is H3PW_(12)O_(40)xH_(2)O and P-UCNS is phosphoric acid-modified unstack graphitic carbon nitride)by incorporating phosphotungstic acid on phosphoric acid-functionalised graphitic carbon nitride(g-C_(3)N_(4))nanosheets.The performance of PW_(12)-P-UCNS was tested using the benzyl alcohol photo-oxidation reaction to produce benzaldehyde in H_(2)O,at room temperature(20℃).The asprepared PW12-P-UCNS photocatalyst showed excellent photocatalytic performance with 58.3%conversion and 99.5%selectivity within 2 h.Moreover,the catalyst could be reused for at least five times without significant activity loss.Most importantly,a proposed Z-scheme mechanism of the PW_(12)-P-UCNScatalysed model reaction was revealed.We carefully investigated its transient photocurrent and electrochemical impedance,and identified superoxide radicals and photogenerated holes as the main active species through electron spin-resonance spectroscopy and scavenger experiments.Results show that the designed PW_(12)-P-UCNS photocatalyst is a highly promising candidate for benzaldehyde production through the photo-oxidation reaction in aqueous phase,under mild conditions.

关 键 词：Photocatalysis HETEROPOLYACIDS Graphitic carbon nitride BENZALDEHYDE 

分 类 号：TQ243.4[化学工程—有机化工] TQ426