FULL PAPER Active and recyclable ordered mesoporous magnetic organometallic catalyst as high‐performance visible light photocatalyst for degradation of organic pollutants Razieh Nejat 1 | Masoumeh Chamack 2 | Alireza Mahjoub 2 1 Chemistry Department, Faculty of Science, Kosar University of Bojnord, Bojnord, Iran 2 Chemistry Department, Tarbiat Modares University, PO Box 14155‐4838, Tehran, Iran Correspondence Razieh Nejat, Chemistry Department, Faculty of Science, Kosar University of Bojnord, Bojnord, Iran. Email: organochem_nejat@yahoo.com A novel light‐active magnetic Pd complex as a photocatalyst was prepared through bonding organometallics to mesoporous silica channels formed on the surface of silica‐coated iron oxide nanoparticles. The nanocomposite (denoted as Fe 3 O 4 @SiO 2 @m‐SiO 2 @PDA‐Pd(0); PDA = 1,10‐phenanthroline‐2,9‐dicarbaldehyde) is more efficient and has higher photocatalytic capability in the degradation of 2,4‐ dichlorophenol under visible light irradiation compared with virgin Pd complex (PDA‐Pd). This noteworthy photodegradation activity can be due to the high dispersion of Pd nanoparticles. High yield, low reaction time and non‐toxicity of the catalyst are the main merits of this protocol. Also magnetic separation is an environmentally friendly alternative method for the separation and recovery of the catalyst, since it minimizes the use of solvents and auxiliary materials, reduces operation time and minimizes catalyst loss by preventing mass loss and oxidation. The produced Pd catalyst was characterised using various techniques. Furthermore, transmission electron microscopy characterization was used for determining the structural properties of the Pd nanocatalyst. KEYWORDS 2,4‐dichlorophenol, magnetic Pd photocatalyst, visible light irradiation 1 | INTRODUCTION Chlorophenols, which are widely used for producing various compounds in the chemical industry, are considered as harm- ful organic pollutants in water because of their toxicity and harmful effects on the human nervous system. [1] Hence, many studies have been conducted to investigate how to degrade and remove these harmful pollutants from wastewa- ter. The stable C─Cl bond, which makes them harmful, is also responsible for their persistence and formation of highly toxic by‐products during their degradation via advanced oxidation processes. [2] So, heterogeneous photocatalysis systems which can completely mineralize chlorinated phe- nols in the presence of solar radiation as source of energy and air as oxidant have received much interest. [3–5] Recent reports describe organometallic complexes composed of a reactive metal centre as photocatalytic sys- tems. [6–11] These complexes were selected as photosensi- tizers that possess excellent photophysical properties such as an intense absorption in the visible region and a long excited‐state lifetime. Schiff base ligands are suitable for maintaining light‐absorbing properties and introducing metal centres in close proximity. [12–14] It has been reported that in comparison to homogeneous systems, immobilization of metal complexes onto solid supports with high surface area leads to several advantages. More facile recovery and greater efficiency of reactions occurring in the presence of supported metal complexes are among the advantages. Since the development of the M41S family, incorporation of transition metal complexes Received: 11 November 2016 Revised: 24 December 2016 Accepted: 31 December 2016 DOI 10.1002/aoc.3745 Appl Organometal Chem. 2017;e3745. https://doi.org/10.1002/aoc.3745 Copyright © 2017 John Wiley & Sons, Ltd. wileyonlinelibrary.com/journal/aoc 1 of 9