Microwave-assisted preparation of flower-like cobalt phosphate and its application as a new heterogeneous Fenton-like catalyst

摘要

A novel flower-like 3D hierarchical cobalt phosphate Co-3(PO4)(2).8H(2)O (fCoP), and a plate-like cobalt phosphate (pCoP) were successfully synthesized via a microwave-assisted method at low temperature under atmospheric pressure using hexamethylene tetramine (HMTA) or urea as a template. All CoPs were characterized using XRD, FESEM, TEM, DRS and surface photovoltage spectra (SPS). The performance of the photocatalytic degradation of Rhodamine B (RhB) via a Fenton-like process on CoPs was evaluated both in the dark and under illumination. The results showed that the morphology and composition of the CoPs affected the RhB degradation. The flower-like hierarchical fCoP favored the photo degradation of RhB. fCoP was also confirmed to have the merits of easy recycling and good stability based on successive degradation experiments. The active species trapping experiments showed that the superoxide radical (center dot O-2(-)) was the dominant active species in the Fenton-like process. The catalytic activation was confirmed to be related to both the Co(II) on the surface and the fCoP framework. (C) 2016 Elsevier B.V. All rights reserved.