Spontaneous Formation of Noble- and Heavy-Metal-Free Alloyed Semiconductor Quantum Rods for Efficient Photocatalysis

Dechao Chen; Huayang Zhang; Yunguo Li; Yingping Pang; Zongyou Yin; Hongqi Sun; Lai-Chang Zhang; Shaobin Wang; Martin Saunders; Emily Barker; Guohua Jia

doi:10.1002/adma.201803351

Spontaneous Formation of Noble- and Heavy-Metal-Free Alloyed Semiconductor Quantum Rods for Efficient Photocatalysis

Adv Mater. 2018 Sep;30(39):e1803351. doi: 10.1002/adma.201803351. Epub 2018 Jul 30.

Authors

Affiliations

¹ Curtin Institute of Functional Molecules and Interfaces, School of Molecular and Life Sciences, Curtin University, GPO Box U1987, WA, 6845, Australia.
² Department of Chemical Engineering and CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), Curtin University, GPO Box U1987, WA, 6845, Australia.
³ Faculty of Mathematical and Physical Sciences, University College London, Gower Street, London, WC1E 6BT, UK.
⁴ Research School of Chemistry, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia.
⁵ School of Engineering, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia.
⁶ Centre for Microscopy, Characterization and Analysis (CMCA), The University of Western Australia, Perth, WA, 6009, Australia.

PMID: 30059172
DOI: 10.1002/adma.201803351

Abstract

Quasi-1D cadmium chalcogenide quantum rods (QRs) are benchmark semiconductor materials that are combined with noble metals to constitute QR heterostructures for efficient photocatalysis. However, the high toxicity of cadmium and cost of noble metals are the main obstacles to their widespread use. Herein, a facile colloidal synthetic approach is reported that leads to the spontaneous formation of cadmium-free alloyed ZnS_x Se_1-_x QRs from polydisperse ZnSe nanowires by alkylthiol etching. The obtained non-noble-metal ZnS_x Se_1-_x QRs can not only be directly adopted as efficient photocatalysts for water oxidation, showing a striking oxygen evolution capability of 3000 µmol g^-1 h^-1 , but also be utilized to prepare QR-sensitized TiO₂ photoanodes which present enhanced photo-electrochemical (PEC) activity. Density functional theory (DFT) simulations reveal that alloyed ZnS_x Se_1-_x QRs have highly active Zn sites on the (100) surface and reduced energy barrier for oxygen evolution, which in turn, are beneficial to their outstanding photocatalytic and PEC activities.

Keywords: alloyed quantum rods; heavy-metal-free; noble-metal-free; oxygen evolution reaction; photocatalysis.

Abstract

Grants and funding