title: Controllable synthesis of concave cubic gold core-shell nanoparticles for plasmon-enhanced photon harvesting.
abstract: Well-defined core-shell nanoparticles (NPs) containing concave cubic Au cores and TiO2 shells (CA@T) were synthesized in colloidal suspension. These CA@T NPs exhibit Localized Surface Plasmon Resonance (LSPR) absorption in the NIR region, which provides a unique property for utilizing the low energy range of the solar spectrum. In order to evaluate the plasmonic enhancement effect, a variety of CA@T NPs were incorporated into working electrodes of dye-sensitized solar cells (DSSCs). By adjusting the shell thickness of CA@T NPs, the plasmonic property can be tuned to achieve maximum photovoltaic improvement. Furthermore, the DSSC cells fabricated with the CA@T NPs exhibit a remarkably plasmonic assisted conversion efficiency enhancement (23.3%), compared to that (14.8%) of the reference cells assembled with spherical Au@TiO2 core-shell (SA@T) NPs under similar conditions. Various characterizations reveal that this performance improvement is attributed to the much stronger electromagnetic field generated at the hot spots of CA@T NPs, resulting in significantly higher light harvesting and more efficient charge separation. This study also provides new insights into maximizing the plasmonic enhancement, offering great potential in other applications including light-matter interaction, photocatalytic energy conversion and new-generation solar cells.
authors.affiliation: Nanomaterials Centre, School of Chemical Engineering and AIBN, The University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Yang
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Nanomaterials Centre, School of Chemical Engineering and AIBN, The University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Teera
authors.initials: T
authors.lastname: Butburee
authors.affiliation: Nanomaterials Centre, School of Chemical Engineering and AIBN, The University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Hua
authors.initials: H
authors.lastname: Yu
authors.affiliation: Institute of Superconducting and Electronic Materials, Australian Institute of Innovative Materials, The University of Wollongong, North Wollongong, NSW 2500, Australia.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: School of Chemical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Rose
authors.initials: R
authors.lastname: Amal
authors.affiliation: Nanomaterials Centre, School of Chemical Engineering and AIBN, The University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: G Q Max
authors.initials: GQ
authors.lastname: Lu
authors.affiliation: Nanomaterials Centre, School of Chemical Engineering and AIBN, The University of Queensland, Brisbane, QLD 4072, Australia. Electronic address: l.wang@uq.edu.au.
authors.forename: Lianzhou
authors.initials: L
authors.lastname: Wang
keywords: Au@TiO(2) core–shell nanoparticle; Dye-sensitized solar cells; Hot spot; Plasmonic enhancement