Nano-ceramic support materials for low temperature fuel cell catalysts

Abstract

Low temperature fuel cells (LTFCs) have received broad attention due to their low operating temperature, virtually zero emissions, high power density and efficiency. However, the limited stability of the catalysts is a critical limitation to the large scale commercialization of LTFCs. State of the art carbon supports undergo corrosion under harsh chemical and electrochemical oxidation conditions, which results in performance degradation of catalysts. Therefore, non-carbon materials which are highly oxidation resistant under strongly oxidizing conditions of LTFCs are ideal alternative supports. This minireview highlights the advances and scenarios in using nano-ceramics as supports to enhance the stability of catalysts, the solutions to improve electrical conductivity of nano-ceramic materials, and the synergistic effects between metal catalyst and support to help improve the catalytic activity and CO/SO2 tolerance of catalysts.

Electronic structure modification of platinum on titanium nitride resulting in enhanced catalytic activity and durability for oxygen reduction and formic acid oxidation

“…A strong metal-support interaction (SMSI) between Pt and ceramic supports has been used to simultaneously improve the activity and durability of Pt catalysts [16,17]. A strong interaction usually increases the Pt dispersion and causes the lower particle aggregation, because small Pt nanoparticles are more strongly anchored to the support.…”

Kinetic Role of Carbon in Solid-State Synthesis of Zirconium Diboride using Nanolaminates: Nanocalorimetry Experiments and First-Principles Calculations

“…Examples include its use as a substrate for group III nitride semiconductors in optoelectronic devices [1][2][3][4][5] , as support material for low-temperature fuel cells 6,7 , and as a hydrogen storage medium 8 . Difficulties associated with synthesis, however, have hindered broad adoption of the material -production of high-density ZrB 2 typically requires both extremely high temperature and pressure 9 because of its high melting point and stability.…”

Improving catalyst stability in nano-structured solar and fuel cells

“…It was shown that no change in the redox region occurred after 48 h oxidation treatment for nano-ZrO 2 ceramic [141]. Furthermore, different electrochemical inert ceramics including metal oxides (TiO 2 ), nitrides (TiN, ZrN), borides (TiB 2 ) and carbides (TaC) are reported as stable replacements for traditional carbon black support [103,135]. In a comparative study, TiO 2 supported Pt electrocatalyst showed promising stability when aged at 1.2 V for a corrosion time of 200 h, whereas the carbon supported Pt electrocatalyst degraded within 80 h [98].…”

“…Pt based nanoparticles are reported to be degrading under electrochemical oxidation conditions and corrosive environment due to decrease in chemical surface area, particles aggregation or migration, dissolution or redeposition (Oswald ripening process) and detachment due to corrosion of the C support [135,136,75,137,138]. Ultrathin Pt monolayer shell Pd nanowire core catalysts have shown excellent electrochemical stability under accelerated half-cell testing with an increase in area-specific activity by 1.5-folds [139].…”