Tailoring sub-5 nm Fe-doped CeO_(2)nanocrystals within confined spaces to boost photocatalytic hydrogen evolution under visible light  

作　　者：Giuseppina Iervolino Olimpia Tammaro Marco Fontana Bruno Masenelli Anne D.Lamirand Vincenzo Vaiano Serena Esposito 

机构地区：[1]Department of Industrial Engineering,University of Salerno,Via Giovanni Paolo II 132,84084 Fisciano,SA,Italy [2]Department of Applied Science and Technology and INSTM Unit of Torino-Politecnico,Politecnico di Torino,Corso Duca degli Abruzzi 24,10129 Torino,Italy [3]Center for Sustainable Future Technologies POLITO,Istituto Italiano di Tecnologia,Via Livorno 60,10144 Turin,Italy [4]INSA Lyon,Ecole Centrale de Lyon,CNRS,Universite Claude Bernard Lyon 1,CPE Lyon,INL,UMR5270,69621 Villeurbanne,France

出　　处：《Journal of Energy Chemistry》2025年第2期263-277,I0007,共16页能源化学(英文版)

基　　金：funding from the"Ministero dell'Universitàe della Ricerca(MUR)"(Italy)under the"Dipartimento di Eccellenza 2018-2022"program.

摘　　要：This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.

关 键 词：Sub-5nm Fe-doped CeO_(2) Hydrogen evolution Photocatalysis Visible light Reverse micelles Mesoporous CeO_(2) 

分 类 号：X70[环境科学与工程—环境工程]