New insights into the relationship between structure and photocatalytic properties of TiO₂ catalysts

TY - JOUR

T1 - New insights into the relationship between structure and photocatalytic properties of TiO2 catalysts

AU - Veres, Ágnes

AU - Ménesi, Judit

AU - Janáky, Csaba

AU - Samu, Gergely F.

AU - Scheyer, Martin Karl

AU - Xu, Qisong

AU - Salahioglu, Fatma

AU - Garland, Marc V.

AU - Dékány, Imre

AU - Zhong, Ziyi

N1 - Publisher Copyright: © The Royal Society of Chemistry 2015.

PY - 2015/11/14

Y1 - 2015/11/14

N2 - This work systematically investigated the relationship between structure, morphology, photoelectrochemical (PEC) and photocatalytic (PC) properties of TiO2 catalysts. A series of TiO2 catalysts with various phase compositions (anatase-, brookite- and finally rutile-rich samples) and morphologies (1D morphology, rhomboid nanoparticles (NPs) and flower-like assemblies of nanorods) were prepared by an acidic hydrothermal treatment of hydrogen titanate nanofibres (H-TNFs). The structures of the samples, such as crystal phase composition and their spatial distribution, were extensively characterised, and the samples were tested for photocatalytic degradation of ethanol. A strong correlation is found between PEC and PC properties. PEC measurements revealed that the brookite-rich samples generated high but unstable photocurrents. The anatase and rutile-rich samples showed good stability, but for the rutile-rich samples low photocurrents were detected due to the poor conductivity of this polymorph. In contrast, the sample containing 93.2% anatase and 6.8% brookite with elongated morphology not only showed the ability to generate high photocurrents but also maintained a stable photoresponse upon an extended period of time, because of its well-balanced bi-crystalline structure and elongated morphology. Therefore, the abilities to generate high photocurrents and to maintain a stable photoresponse are equally important and probably a prerequisite for a good photocatalyst.

AB - This work systematically investigated the relationship between structure, morphology, photoelectrochemical (PEC) and photocatalytic (PC) properties of TiO2 catalysts. A series of TiO2 catalysts with various phase compositions (anatase-, brookite- and finally rutile-rich samples) and morphologies (1D morphology, rhomboid nanoparticles (NPs) and flower-like assemblies of nanorods) were prepared by an acidic hydrothermal treatment of hydrogen titanate nanofibres (H-TNFs). The structures of the samples, such as crystal phase composition and their spatial distribution, were extensively characterised, and the samples were tested for photocatalytic degradation of ethanol. A strong correlation is found between PEC and PC properties. PEC measurements revealed that the brookite-rich samples generated high but unstable photocurrents. The anatase and rutile-rich samples showed good stability, but for the rutile-rich samples low photocurrents were detected due to the poor conductivity of this polymorph. In contrast, the sample containing 93.2% anatase and 6.8% brookite with elongated morphology not only showed the ability to generate high photocurrents but also maintained a stable photoresponse upon an extended period of time, because of its well-balanced bi-crystalline structure and elongated morphology. Therefore, the abilities to generate high photocurrents and to maintain a stable photoresponse are equally important and probably a prerequisite for a good photocatalyst.

UR - http://www.scopus.com/inward/record.url?scp=84916937464&partnerID=8YFLogxK

U2 - 10.1039/c4ra11489b

DO - 10.1039/c4ra11489b

M3 - 文章

AN - SCOPUS:84916937464

SN - 2046-2069

VL - 5

SP - 2421

EP - 2428

JO - RSC Advances

JF - RSC Advances

IS - 4

ER -