Hydroxyapatite‐Graphene Oxide Nanocomposite with Enhanced Ammonia Sensing Property

Abstract

AbstractThis study is focused on presenting a new approach for utilizing properties of hydroxyapatite (HAp) and carbon‐containing material in sensing applications. Nanocrystalline HAp and graphene oxide (GO) are synthesized by wet chemical precipitation and Hummer's method, respectively. A nanocomposite based on HAp and 2 wt % concentration of GO is prepared just by a mechanically mixing method. A simple and cost‐effective screen printing technique is utilized for the development of thick films on a glass substrate. The ammonia‐sensing properties of the nanocrystalline material HAp and 2 wt% GO‐doped HAp are investigated by two‐probe electric method. The gas‐sensing parameters like operating temperature, response/recovery time, maximum detection limit, etc., are studied. The best sensing performance is shown by 2 wt% GO doped HAp thick film for the detection of 10 ppm of ammonia at 35 °C, i.e., its operating temperature than the pure HAp. The maximum uptake capacity of ammonia for 2 wt% GO doped HAp is found to be very high, i.e., 2000 ppm compared to the pure HAp, i.e., 1200 ppm. Whereas other parameters like response and recovery time at corresponding operating temperatures are nearly the same for both sensing substrates.