Staff directory Yongchao Zhang

Yongchao Zhang

Senior Postdoctoral Researcher
yongchao.zhang(ELIMINAR)@icn2.cat
Advanced Electron Nanoscopy

Publications

2015

  • Cu2ZnSnS4-Ag2S Nanoscale p-n Heterostructures as Sensitizers for Photoelectrochemical Water Splitting

    Yu X., Liu J., Genç A., Ibáñez M., Luo Z., Shavel A., Arbiol J., Zhang G., Zhang Y., Cabot A. Langmuir; 31 (38): 10555 - 10561. 2015. 10.1021/acs.langmuir.5b02490. IF: 4.457

    A cation exchange-based route was used to produce Cu2ZnSnS4 (CZTS)-Ag2S nanoparticles with controlled composition. We report a detailed study of the formation of such CZTS-Ag2S nanoheterostructures and of their photocatalytic properties. When compared to pure CZTS, the use of nanoscale p-n heterostructures as light absorbers for photocatalytic water splitting provides superior photocurrents. We associate this experimental fact to a higher separation efficiency of the photogenerated electron-hole pairs. We believe this and other type-II nanoheterostructures will open the door to the use of CZTS, with excellent light absorption properties and made of abundant and environmental friendly elements, to the field of photocatalysis. © 2015 American Chemical Society.


  • Cu2ZnSnS4-PtM (M = Co, Ni) Nanoheterostructures for Photocatalytic Hydrogen Evolution

    Yu X., An X., Genç A., Ibáñez M., Arbiol J., Zhang Y., Cabot A. Journal of Physical Chemistry C; 119 (38): 21882 - 21888. 2015. 10.1021/acs.jpcc.5b06199. IF: 4.772

    We report the synthesis and photocatalytic and magnetic characterization of colloidal nanoheterostructures formed by combining a Pt-based magnetic metal alloy (PtCo, PtNi) with Cu2ZnSnS4 (CZTS). While CZTS is one of the main candidate materials for solar energy conversion, the introduction of a Pt-based alloy on its surface strongly influences its chemical and electronic properties, ultimately determining its functionality. In this regard, up to a 15-fold increase of the photocatalytic hydrogen evolution activity was obtained with CZTS-PtCo when compared with CZTS. Furthermore, two times higher hydrogen evolution rates were obtained for CZTS-PtCo when compared with CZTS-Pt, in spite of the lower precious metal loading of the former. Besides, the magnetic properties of the PtCo nanoparticles attached to the CZTS nanocrystals were retained in the heterostructures, which could facilitate catalyst purification and recovery for its posterior recycling and/or reutilization. © 2015 American Chemical Society.