Premium
Broadband Hot‐Electron Collection for Solar Water Splitting with Plasmonic Titanium Nitride
Author(s) -
Naldoni Alberto,
Guler Urcan,
Wang Zhuoxian,
Marelli Marcello,
Malara Francesco,
Meng Xiangeng,
Besteiro Lucas V.,
Govorov Alexander O.,
Kildishev Alexander V.,
Boltasseva Alexandra,
Shalaev Vladimir M.
Publication year - 2017
Publication title -
advanced optical materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.89
H-Index - 91
ISSN - 2195-1071
DOI - 10.1002/adom.201601031
Subject(s) - materials science , plasmon , tin , titanium nitride , optoelectronics , nanoparticle , nanowire , nanotechnology , water splitting , surface plasmon resonance , photocatalysis , nitride , metallurgy , layer (electronics) , biochemistry , chemistry , catalysis
The use of hot electrons generated from the decay of surface plasmons is a novel concept that promises to increase the conversion yield in solar energy technologies. Titanium nitride (TiN) is an emerging plasmonic material that offers compatibility with complementary metal‐oxide‐semiconductor (CMOS) technology, corrosion resistance, as well as mechanical strength and durability, thus outperforming noble metals in terms of cost, mechanical, chemical, and thermal stability. Here, it is shown that plasmonic TiN can inject into TiO 2 twice as many hot electrons as Au nanoparticles. TiO 2 nanowires decorated with TiN nanoparticles show higher photocurrent enhancement than decorated with Au nanoparticles for photo‐electrochemical water splitting. Experimental and theoretical evidence highlight the superior performance of TiN in hot carrier collection due to several factors. First, TiN nanoparticles provide broadband absorption efficiency over the wavelength range 500–1200 nm combined with high field enhancement due to its natural cubic morphology. Second, TiN forms an Ohmic junction with TiO 2 , thus enabling efficient electron collection compared to Au nanoparticles. Since TiN nanoparticles have strong plasmon resonances in the red, the entire solar spectrum is covered when complemented with Au nanocrystals. These findings show that transition metal nitrides enable plasmonic devices with enhanced performance for solar energy conversion.