Oxidative decomposition of volatile organic compound on hydroxyapatite with oriented crystal structures

Abstract

Hydroxyapatite (HAp) exhibits superior biocompatibility, ion-exchange ability and high adsorption property has attracted much attention as one of the most well-known ceramic functional materials. We have previously reported the efficient oxidative decomposition of volatile organic compounds (VOC) on commercial HAp powders, which makes HAp a promising alternative material of precious metal nanoparticle catalyst for environmental purification. In this work, HAp with oriented crystal growth of a-plane and c-plane were synthesized via air-liquid interface precipitation in solution, and the influence of crystal orientation on VOC decomposition performance was systemically investigated. As a result, HAp with preferential growth of c-plane performs higher catalytic VOC decomposition activity, which can be attributed to the large number of active radicals generated on surface despites the relative smaller sufficient surface area. The results in this study highlight the important relation between crystal structure of HAp and the decomposition activity of VOC, which also provide useful information for the structure design of ceramic functional materials.