Synthesis of Co3O4/GQD and Co3O4/Zn-ICP Nanocomposites for Photocatalytic Degradation of Rhodamine B (RhB)

Wastewater release from industries is a serious environmental problem. Especially, the discharge of these dyes contained wastewater, which is not only causing irritation of the skin, eyes and respiratory tract but also in many cases carcinogenic to humans and animals [1]. Rhodamine B (RhB) has wide industrial application, but causes serious environmental problems because of its high toxicity and accumulation in the environment. Till now, many efforts have been done for removal or separation of RhB from water. One of the effective methods for decreasing water pollutants is their photocatalytic degradation [2]. Co3O4 has dual attractive properties for its magnetic and semiconducting properties. Co3O4 nanostructures has found potential application in different fields such as supercapacitor, photoelectrochemical water splitting, gas sensor, and lithium ion batteries.In this work, we have developed a facile and inexpensive way to access new nanocomposites that have some properties in degradation of Rhodamine B dye. First, Co3O4-QDs with size of about 3 nm was synthesized via co-precipitation method [3]. Graphene quantum dots (QDs) were synthesized via pyrolysis of citric acid and zinc containing infinite coordination polymer (Zn-ICP) was obtained by aminoterephthalic acid as ligand. Co3O4-QDs were deposited on GQD and Zn-ICP to achieve Co3O4/GQD and Co3O4 /Zn-ICP. Then, they were characterized by FT-IR spectroscopy, FE-SEM analysis, X-ray diffraction (XRD), UV-VIS-DRS and EDX spectroscopies and EDX mapping. These nanocomposites were used for photocatalytic degradation of Rhodamine B under visible light irradiation for 180 min and samples were taken from it every 30 min. Scavenger test were also done by addition of EDTA, benzoquinone, and 2-propanol. UV-Vis analysis shows that the efficiency of RhB degradation in the presence of Co3O4/GQD and Co3O4/ Zn-ICP were 93% and 89%, respectively.

Keywords:

Co3O4 , Quantum dot , Nanocomposite , Photocatalytic degradation