title: Plasmonic near-touching titanium oxide nanoparticles to realize solar energy harvesting and effective local heating.
abstract: Through the excitation of plasmon resonance, the energy of plasmonic nanoparticles either reradiates through light scattering or decays into energetic electrons (absorption). The plasmon-induced absorption can greatly enhance the efficiency of solar energy harvesting, local heating, photodetection and photocatalysis. Here, we demonstrate that heavily self-doped titanium oxide nanoparticles (TiO1.67 analogue arising from oxygen vacancies in rutile TiO2) with the plasmon resonance dominated by an interband transition shows strong absorption to build a broadband perfect absorber in the wavelength range from 300 to 2000 nm covering the solar irradiation spectrum completely. The absorptivity of the fabricated array is greater than 90% in the whole spectral range. And the broadband and strong absorption is due to the plasmon hybridization and hot spot generation from near-touching TiO1.67 nanoparticles with different sizes. What is more, the local heating of a TiO1.67 nanoparticle layer is fast and effective. The temperature increases quickly from 30 °C to 80 °C within 200 seconds. This local heating can realize rapid solar-enabled evaporation which can find applications in large-scale distillation and seawater desalination. These findings actually open a pathway for applications of these newly developed plasmonic materials in the energy and environment fields.
authors.affiliation: State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, School of Physics & Engineering, Sun Yat-sen University, Guangzhou 510275, Guangdong, P. R. China. stsygw@mail.sysu.edu.cn.
authors.forename: Jiahao
authors.initials: J
authors.lastname: Yan
authors.forename: Pu
authors.initials: P
authors.lastname: Liu
authors.forename: Churong
authors.initials: C
authors.lastname: Ma
authors.forename: Zhaoyong
authors.initials: Z
authors.lastname: Lin
authors.forename: Guowei
authors.initials: G
authors.lastname: Yang