Strong interfacial charge transfer between hausmannite manganese oxide and alumina for efficient photocatalysis  

作　　者：Aisha Kanwal Shamaila Sajjad Sajjad Ahmed Khan Leghari Muhammad Naeem Khan 

机构地区：[1]International Islamic University,H-10 Islamabad,Pakistan [2]Pakistan Institute of Engineering and Applied Sciences,Islamabad 44000,Pakistan [3]Department of Chemistry,Government College of Science,Lahore,Pakistan

出　　处：《Chinese Journal of Chemical Engineering》2021年第5期147-159,共13页中国化学工程学报（英文版）

基　　金：The work is acknowledged to H-10,Islamabad,Higher Education of Commission of Pakistan (NRPU Grant No. 3660);International Islamic University,H-10,Islamabad,and Pakistan Institute of Engineering and Applied Sciences. We are very much grateful to School of Environmental and Chemical Engineering,Shanghai Jiao Tong University,Shanghai,China,University of the Punjab Lahore,Government College University Lahore,National Centre of Physics,Institute of Space Technology and Allama Iqbal Open University Islamabad for analysis.

摘　　要：Well crystalline manganese oxide(Mn_(3)O_(4))nanoparticles anchored on gamma alumina(γ-Al_(2)O_(3))have been successfully tailored via a proficient and cost effective chemical process as an efficient material for photo catalysis.XRD indicated the composite formation ofγ-Al_(2)O_(3) and hausmannite structure of Mn_(3)O_(4).SEM and TEM revealed that hetero structure of Mn_(3)O_(4)/γ-Al_(2)O_(3) exhibits an amalgam of aggregated nanoparticles and nanorods.XPS demonstrated the chemical states of binary nanocomposite.The band gap tuning has been performed withγ-Al_(2)O_(3) nanoparticles by assimilating hausmannite Mn_(3)O_(4) particles into flower like microstructure of Al_(2)O_(3).The photoluminescence spectra affirmed the enhancement in charge separation in Mn_(3)O_(4)/γ-Al_(2)O_(3) binary hybrid photocatalyst.The band gap becomes narrow with the increase in concentrations of Mn_(3)O_(4).The narrowing of band gap is concorded with crystalline domains of primary aggregated particles.To elucidate the mechanism of the photocatalytic activity linear sweep voltammetry was performed.The results showed that Mn_(3)O_(4)/γ-Al_(2)O_(3) nanocomposite revealed the enhancement in current density as compared to pureγ-Al_(2)O_(3) which confirmed the electron transfer from Mn_(3)O_(4) toγ-Al_(2)O_(3) through the interfacial potential gradient in conduction bands.The optimum concentration of 6.0%Mn_(3)O_(4)/γ-Al_(2)O_(3) for hybrid structure showed an excellent photocatalytic activity under visible light due to narrow band gap energy.High degree distribution of Mn_(3)O_(4) nano architects overlying onγ-Al_(2)O_(3) induces a significant synergic effect betweenγ-Al_(2)O_(3) and hausmannite phase of manganese oxide(Mn_(3)O_(4)).This strong interfacial contact betweenγ-Al_(2)O_(3) and Mn_(3)O_(4) endures the quick transfer of photo generated charge carriers across interface.

关 键 词：HAUSMANNITE Mn_(3)O_(4) ALUMINA Band gap tuning INTERFACIAL charge transfer NANOMATERIALS Catalysis 

分 类 号：O643.36[理学—物理化学] O644.1[理学—化学]