Tag Archives: Titanium Nitride Nanoparticles as Plasmonic Solar Heat Transducers

Trying to push past the 30% energy conversion ceiling for solar cells

A Nov. 21, 2016 news item on Nanowerk describes some work in Japan which suggests that more energy conversion for solar cells is possible,

Solar energy could provide a renewable, sustainable source of power for our daily needs. However, even the most state-of-the-art solar cells struggle to achieve energy conversion efficiency of higher than 30%. While current solar-powered water heaters fare better in terms of energy efficiency, there are still improvements to be made if the systems are to be used more widely.

One potential candidate for inclusion in solar water heaters is “nanofluid,” that is, a liquid containing specially-designed nanoparticles that are capable of absorbing sunlight and transforming it into thermal energy in order to heat water directly.

A Nov. 20, 2016 (Japan) International Center for Materials Nanoarchitectonics (WPI-MANA) press release (received via email), explains further,

Nanoparticle Boost for Solar-powered Water Heating

Now, Satoshi Ishii and his co-workers at the International Center for Materials Nanoarchitectonics (WPI-MANA) and the Japan Science and Technology Agency have developed a new nanofluid containing titanium nitride (TiN) nanoparticles, which demonstrates high efficiency in heating water and generating water vapor.

The team analytically studied the optical absorption efficiency of a TiN nanoparticle and found that it has a broad and strong absorption peak thanks to lossy plasmonic resonances. Surprisingly, the sunlight absorption efficiency of a TiN nanoparticle outperforms that of a carbon nanoparticle and a gold nanoparticle.

They then exposed each nanofluid to sunlight and measured its ability to heat pure water. The TiN nanofluid had the highest water heating properties, stemming from the resonant sunlight absorption. It also generated more vapor than its carbon‒based counterpart. The efficiency of the TiN nanofluid reached nearly 90 %. Crucially, the TiN particles were not consumed during the process, meaning a TiN‒based heating system could essentially be self‒sustaining over time.

TiN nanofluids show great promise in solar heat applications, with high potential for use in everyday appliances such as showers. The new design could even contribute to methods for decontaminating water through vaporization.

90% is a very exiting conversion rate. Of course, now they need to make sure they can achieve those results consistently, get those results outside the laboratory, and scale up to industrial standards.

Here’s a link to and a citation for the paper,

Titanium Nitride Nanoparticles as Plasmonic Solar Heat Transducers by Satoshi Ishii, Ramu Pasupathi Sugavaneshwar, and Tadaaki Nagao. J. Phys. Chem. C, 2016, 120 (4), pp 2343–2348 DOI: 10.1021/acs.jpcc.5b09604 Publication Date (Web): December 21, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall and it’s almost a year old. I wonder what occasioned the push for publicity.