Self-Assembled Au/CdSe Nanocrystal Clusters for Plasmon-Mediated Photocatalytic Hydrogen Evolution

5 years ago

Self-Assembled Au/CdSe Nanocrystal Clusters for Plasmon-Mediated Photocatalytic Hydrogen Evolution

Yanjun Bao, Tierui Zhang, Yadong Yin, Zheyu Fang, Li-Zhu Wu, Yufei Zhao, Yinhu Cao, Chen-Ho Tung, Geoffrey I. N. Waterhouse, Run Shi

Plasmon-mediated photocatalytic systems generally suffer from poor efficiency due to weak absorption overlap and thus limited energy transfer between the plasmonic metal and the semiconductor. Herein, a near-ideal plasmon-mediated photocatalyst system is developed. Au/CdSe nanocrystal clusters (NCs) are successfully fabricated through a facile emulsion-based self-assembly approach, containing Au nanoparticles (NPs) of size 2.8, 4.6, 7.2, or 9.0 nm and CdSe quantum dots (QDs) of size ≈3.3 nm. Under visible-light irradiation, the Au/CdSe NCs with 7.2 nm Au NPs afford very stable operation and a remarkable H2-evolution rate of 73 mmol gCdSe−1 h−1 (10× higher than bare CdSe NCs). Plasmon resonance energy transfer from the Au NPs to the CdSe QDs, which enhances charge-carrier generation in the semiconductor and suppresses bulk recombination, is responsible for the outstanding photocatalytic performance. The approach used here to fabricate the Au/CdSe NCs is suitable for the construction of other plasmon-mediated photocatalysts. Highly efficient plasmon-mediated photocatalysts based on Au/CdSe nanocrystal clusters (NCs) are successfully fabricated through an emulsion-based self-assembly approach. The Au/CdSe NCs synergistically harness the excellent visible-light-absorption properties of CdSe quantum dots and Au nanoparticles, affording a remarkable H2 evolution rate of 73 mmol gCdSe−1 h−1 in aqueous solution under visible-light illumination and excellent operational stability.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/adma.201700803