Synthesis and gas sensing properties of biomorphic LaFeO3 hollow fibers templated from cotton

Biomorphic LaFeO3 hollow fibers with porous walls have been fabricated using cotton as biotemplates. Cotton fibers are infiltrated with lanthanum nitrate and ferric nitrate solution and subsequently sintered in air at high temperatures to produce the final LaFeO3 hollow fibers. The samples have further distinctions in structure, morphology and crystallite size of the nanocrystallites, BET surface area, and the pore size distribution. Growth mechanism of LaFeO3 hollow fibers was proposed. Furthermore, gas sensors were fabricated and an investigation of CO sensing properties has been conducted. Compared with LaFeO3 particles, the hollow fibers display much better CO sensing properties, which is mainly due to the increasing of active surface area and gas diffusion.