Tunnel-Structured Phosphate Exhibiting High Proton Conductivity and Thermal Stability over a Wide Intermediate Temperature RangeClick to copy article linkArticle link copied!
- Yasuaki Matsuda*Yasuaki Matsuda*Email: [email protected]Department of Applied Chemistry, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma,Narashino ,Chiba 275-0016, JapanMore by Yasuaki Matsuda
- Jun NakajimaJun NakajimaDepartment of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1 Ohmiya, Asahi-Ku ,Osaka 535-8585, JapanMore by Jun Nakajima
- Yuta InoueYuta InoueDepartment of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1 Ohmiya, Asahi-Ku ,Osaka 535-8585, JapanMore by Yuta Inoue
- Akihisa IshikawaAkihisa IshikawaDepartment of Applied Chemistry, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma,Narashino ,Chiba 275-0016, JapanMore by Akihisa Ishikawa
- Naoya UetaNaoya UetaDepartment of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1 Ohmiya, Asahi-Ku ,Osaka 535-8585, JapanMore by Naoya Ueta
- Daisuke MoriDaisuke MoriDepartment of Chemistry for Materials, Graduate School of Engineering, Mie University, 1577 Kurimamachiyacho ,Tsu 514-8507, JapanMore by Daisuke Mori
- Sou TaminatoSou TaminatoDepartment of Chemistry for Materials, Graduate School of Engineering, Mie University, 1577 Kurimamachiyacho ,Tsu 514-8507, JapanMore by Sou Taminato
- Nobuyuki ImanishiNobuyuki ImanishiDepartment of Chemistry for Materials, Graduate School of Engineering, Mie University, 1577 Kurimamachiyacho ,Tsu 514-8507, JapanMore by Nobuyuki Imanishi
- Takashi FukushimaTakashi FukushimaDepartment of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1 Ohmiya, Asahi-Ku ,Osaka 535-8585, JapanMore by Takashi Fukushima
- Shinya HigashimotoShinya HigashimotoDepartment of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1 Ohmiya, Asahi-Ku ,Osaka 535-8585, JapanMore by Shinya Higashimoto
Abstract
For the practical application of fuel cells in vehicles, it is a challenge to develop a proton solid electrolyte that coexhibits thermal stability and high proton conductivity at wide intermediate temperatures. Here, we report on the tunnel structured phosphate KNi1–xH2x(PO3)3·yH2O, which exhibits high proton conductivity at room temperature up to 500 °C, with the conductivity value reaching 1.7 × 10–2 S cm–1 at 275 °C for x = 0.18. This material, composed of the smallest cations that form the tunnel framework with face-shared (KO6) and (NiO6) chains and PO4 tetrahedral chains, retained the rigid framework up to 600 °C. Two oxygen sites of water molecules located adjacent to each other along the PO4 tetrahedral chains in the tunnel provided the proton conduction pathway. The sample maintained a conductivity of 5.0 × 10–3 S cm–1 for 10 h at 150 °C while changing the measurement atmosphere to a N2 gas flow, a 4% H2-96% Ar gas flow, and an O2 gas flow. The conductivity value at x = 0.18 obtained from the DC measurement was in the order of 10–6 S cm–1, close to the instrument’s measurement limit. These results demonstrate that tunnel phosphate has potential as a proton solid electrolyte for next-generation fuel cells.
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This article is cited by 4 publications.
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