News from Nanotechjapan


Transparent and Nonflammable Ionogel for Photon Upconversion

 Tokyo Institute of Technology issued a press release on 17th February 2016 that a research group of the institute has succeeded in realizing transparent and nonflammable ionogel applicable to photon upconverters that convert presently wasted sub-bandgap photons to usable higher-energy photons. The results were published in the Journal of Physical Chemistry B* with Associate professor Yoichi Murakami as the senior author.

 They have developed triplet-triplet annihilation (TTA) upconversion ionogel by gelatinizing ionic liquids containing triplet-sensitizing and light-emitting molecules using an ionic gelator. The ionogel absorbs red light with the wavelength of 630 nm, and emits blue light of 480 nm so that red light photon with lower energy is upconverted to blue light photon with higher energy. It shows also optical transparency, nonflammability as well as nonfluidity, which are quite important properties for practical application of ionic-liquid-based photon converter.

 This photon upconverter is expected to find applications in solar cells and photocatalysts for increasing energy conversion efficiency.

*Y. Murakami, Y. Himuro, T. Ito, R. Morita, K. Niimi, and N. Kiyoyanagi, "Transparent and Nonflammable Ionogel Photon Upconverters and Their Solute Transport Properties", Journal of Physical Chemistry B, Vol. 120, No. 4, pp. 748-755 (2016), DOI: 10.1021/acs.jpcb.5b09880; Publication Date (Web): January 11, 2016