3 years ago

Water-free, Proton-Conducting Hybrid Materials for Elevated-Temperature Electrochemical Systems

Water-free, Proton-Conducting Hybrid Materials for Elevated-Temperature Electrochemical Systems
Jalal Jalili, Gabriele Orsini, Vincenzo Tricoli, Maria Beatrice Coltelli
By reacting TiCl4 with nitrilo tris(methylenphosphonic acid) (NTMPA) in water solution, a titanium complex gel (Ti-NTMPA) has been prepared. After drying, this gel was powdered and mixed with benzimidazole. The resulting hybrid material, which is insoluble in water and thermally stable up to at least 210 °C, possesses proton conductivity on the order of 10–2 Ω–1 cm–1 in fully anhydrous conditions. Due to these characteristics, such Ti-NTMPA/benzimidazole hybrid may be considered for application as a proton conductor in fuel cells or water electrolyzers operating under elevated-temperature and low-humidity conditions. X-ray diffraction, thermogravimetric analysis, and FT-IR spectroscopy show the presence of hydrogen-bonding interaction between Ti-NTMPA and benzimidazole in the hybrid. It appears that the Ti-NTMPA/benzimidazole system forms a solid protic ionic with the “free” (not coordinated to Ti) phosphonic acid moieties and benzimidazole acting, respectively, as Bro̷nsted acid and base. In this way the imidazolic rings can vehiculate the protons provided by the phosphonic groups, thereby conferring hopping-site proton conduction upon this hybrid material even in the absence of water. This work provides proof of the above concepts, thereby demonstrating a general paradigm to design a whole class of hybrid materials with effective water-free proton conductivity.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b05742

DOI: 10.1021/acs.jpcc.7b05742

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.