CdS/Au/Ti/Pb(Mg1/3Nb2/3)0.7Ti0.3O3 photocatalysts and biphotoelectrodes with ferroelectric polarization in single domain for efficient water splitting

Impact Factor:

19.503

DOI number:

10.1016/j.apcatb.2018.07.033

Journal:

Appl. Catal. B

Key Words:

Photocatalysis, ferroelectric, polarization, CdS, water splitting, Pb(Mg1/3Nb2/3)0.7Ti0.3O3

Abstract:

The construction of efficient photocatalysts for water splitting is still challenging, mainly due to the unexpected recombination of photogenerated carriers. Ferroelectric polarization-induced charge separation of photocatalysts has been demonstrated as an effective method for improving photocatalytic performance. However, ferroelectric domains in existing works are random before polarization-switching, which results in lower polarization electric field intensity and limits the charge separation efficiency. Here, we report that the spontaneous ferroelectric polarization in a single domain for efficient charge separation over a representative semiconductor CdS, in the form of CdS/Au/Ti/Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (CdS/Au/Ti/PMN-PT), for water splitting in absence of any cocatalyst or external voltage. The photocurrent value of the positive polarized CdS/Au/Ti/PMN-PT yields 1.70 mA·cm−2, which is about 20 times higher than the value of the non-polarized sample. In addition, a biphotoelectrode cell composed of a positively and a negatively polarized CdS/Au/Ti/PMN-PT was constructed. A considerable solar-to-hydrogen conversion efficiency of 0.19% was achieved. It was found that the interfacial resistance and the surface reaction kinetics may be the main factors governing the photocatalytic performance. This work not only provides a strategy to promote charge separation but also develops a new biphotoelectrode cell capable of obtaining efficient solar water splitting.

Co-author:

Bin Hong,Xiaodi Zhu, Fan Zhang. Shikuo Li, Jianjun Ding, Xiaoming Jiang, Chen Gao

First Author:

Zhimin Song

Correspondence Author:

Jun Bao, Song Sun

Document Type:

SCI

Volume:

238

Page Number:

248-254

ISSN No.:

0926-3373

Translation or Not:

no

Date of Publication:

2018-07-11

Links to published journals:

https://www.sciencedirect.com/science/article/pii/S0926337318306416