Facile fabrication of Zr 2 Ni 1 Cu 7 trimetallic nano-alloy and its composite with Si 3 N 4 for visible light assisted photodegradation of methylene blue Gaurav Sharma a,b,c, ⁎, Amit Kumar a,b,c , Shweta Sharma c , Mu. Naushad d , Tansir Ahamad d , Sameerah I. Al-Saeedi e , Ghadah M. Al-Senani e , Nada S. Al-kadhi e , Florian J. Stadler a, ⁎ a College of Materials Science and Engineering, Shenzhen Key Laboratory of Polymer Science and Technology, Guangdong Research Center for Interfacial Engineering of Functional Materials, Nanshan District Key Lab. for Biopolymers and Safety Evaluation, Shenzhen University, Shenzhen 518060, PR China b Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, PR China c School of Chemistry, Shoolini University, Solan 173212, Himachal Pradesh, India d Department of Chemistry, College of Science, King Saud University, Bld.#5, Riyadh, Saudi Arabia e Department of Chemistry, College of Science, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia abstract article info Article history: Received 18 July 2018 Received in revised form 6 September 2018 Accepted 11 September 2018 Available online 13 September 2018 Novel Zr 2 Ni 1 Cu 7 trimetallic nano-alloy (TNA) and Zr 2 Ni 1 Cu 7 /Si 3 N 4 trimetallic nano-alloy composite (TNAC) have been successfully prepared by facile microwave reduction method. The synthesis of TNA and TNAC was ascertained by characterizing them by using various techniques such as SEM, TEM, XRD, EDX and FTIR etc. The EDX shows the presence of all constituents in TNA and TNAC. The XRD study demonstrated the crystalline and semi-crystalline nature of TNA and TNAC. The optical band gap study revealed that TNAC (2.47 eV) has lower band gap then TNA (2.54 eV). The visible light photocatalytic activity of Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC has been successfully utilized for the photodegradation of methylene blue (MB). The presence of H 2 O 2 has been found to influence the photodegradation rate. Photodegradation results presented that maximum deg- radation was observed in the presence of H 2 O 2 and Zr 2 Ni 1 Cu 7 TNAC (92%). Scavenging activity has revealed that the hydroxyl radicals were the major reacting species. These species successfully degraded the MB into various intermediates that has successfully been determined by the LC-MS. Kinetic studies indicated that the degradation of MB by Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC followed pseudo-first-order kinetics. © 2018 Elsevier B.V. All rights reserved. Keywords: Trimetallic nano-alloy Composite Photocatalytic degradation Methylene blue 1. Introduction Nanocomposite materials, composed of more than two phases, are the extensively explored materials having lavishing properties such as high mechanical, electrical, thermal, elastic and optical properties, etc. Number of techniques has been put forward for designing nanocompos- ites which can be categorized into approaches; bottom up and top- down. Combination at the nanoscale provides them high surface area- to- mass ratio that helps in enhancing their adsorbing ability which in turn helps in removing noxious pollutants from environment. Nano- composite materials can also be designed in such a way that it reduces the electron-hole recombination and provide synergistic effect between the constituents that helps in degradation of pollutants. These can be categorized into various forms [1,2] and one such form is nanoalloys. In material chemistry, mixing number of metals helps in extending the properties of the obtained system, generally called alloys or intermediate compounds [3]. Alloying helps in enriching the properties because of optimized composition, structure diversity and synergistic effect between the constituents that increases their utilization in engi- neering, catalysis and electronics etc. [4]. Emergence of nanotechnology has led to the urge to synthesize materials with controllable properties at the nanoscale geometry that has led to the fabrication of nanoalloys [5]. Number of techniques has been suggested for their designing such as electrochemical, radiolysis, sonochemical, biosynthesis, ion implan- tation, co-precipitation and chemical reduction etc. [6,7]. Nanoalloys are of great interest due to their ability of monitoring the physical and chemical properties by varying the composition, atomic ordering and size [8,9]. The engineering properties like tensile and shear strength dif- fer from constituent units whereas physical properties like electrical and thermal conductivity, reactivity, density and Young's modulus, of nanoalloys differ from its individual elemental properties. Pure metals have single melting point but nanoalloys doesn't, inspite they have a range of melting points which consist of blend of solid and liquid phases. The temperature at which the process of melting starts is called solidus and where melting completes is known as liquidus. Number of bimetal- lic and trimetallic nanoalloys have been designed in the recent decades Journal of Molecular Liquids 272 (2018) 170–179 ⁎ Corresponding authors. E-mail addresses: gaurav8777@gmail.com (G. Sharma), fjstadler@szu.edu.cn (F.J. Stadler). https://doi.org/10.1016/j.molliq.2018.09.063 0167-7322/© 2018 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Journal of Molecular Liquids journal homepage: www.elsevier.com/locate/molliq