Hatakeyama Kazuto, Ogata Chikako, Koinuma Michio, Taniguchi Takaaki, Hayami Shinya, Kuroiwa Keita, Matsumoto Yasumichi
Graduate School of Science and Technology, Kumamoto University , 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan.
International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS) , 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
ACS Appl Mater Interfaces. 2015 Oct 21;7(41):23041-6. doi: 10.1021/acsami.5b06470. Epub 2015 Oct 9.
Inexpensive solid proton conducting materials with high proton conductivity and thermal stability are necessary for practical solid state electrochemical devices. Here we report that coal oxide (CO) is a promising carbon-based proton conductor with remarkable thermal robustness. The CO produced by simple liquid-phase oxidation of coal demonstrates excellent dispersibility in water owing to the surface carboxyl groups. The proton conductivity of CO, 3.9 × 10(-3) S cm(-1) at 90% relative humidity, is as high as that of graphene oxide (GO). Remarkably, CO exhibits much higher thermal stability than GO, with CO retaining the excellent proton conductivity as well as the capacitance performance even after thermal annealing at 200 °C. Our study demonstrates that the chemical modification of the abundant coal provides proton conductors that can be used in practical applications for a wide range of energy devices.
对于实用的固态电化学装置而言，具有高质子传导率和热稳定性的廉价固态质子传导材料是必不可少的。在此，我们报道煤氧化物（CO）是一种具有出色热稳定性的、有前景的碳基质子导体。通过煤的简单液相氧化制备的CO由于其表面羧基而在水中表现出优异的分散性。CO在相对湿度90%时的质子传导率为3.9×10⁻³ S cm⁻¹，与氧化石墨烯（GO）相当。值得注意的是，CO表现出比GO高得多的热稳定性，即使在200°C热退火后，CO仍保留优异的质子传导率和电容性能。我们的研究表明，对储量丰富的煤进行化学改性可提供可用于广泛能量装置实际应用的质子导体。
