CERAMICS INTERNATIONAL Available online at www.sciencedirect.com Ceramics International ] (]]]]) ]]]–]]] Simple and rapid synthesis of mesoporous nanosheet-based ZnO hierarchical structure loaded with metal nanoparticles Mark Kenneth Reyes a , Uyanga Dashdorj a , Altangerel Amarjargal a,b , Chan Hee Park a,c,n , Cheol Sang Kim a,c,n a Department of Bionanosystem Engineering, Graduate School, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea b Power Engineering School, Mongolian University of Science and Technology, Ulaanbaatar, Mongolia c Division of Mechanical Design Engineering, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea Received 9 June 2014; received in revised form 22 September 2014; accepted 25 September 2014 Abstract In this paper, mesoporous nanosheet-based ZnO hierarchical structures decorated with Ag nanoparticles were synthesized via a simple, rapid, environment-friendly and cost-effective one pot synthesis approach using NaOH as the precipitating agent. Field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and photoluminescence (PL) spectroscopy were performed in order to investigate the morphology, crystalline structure and molecular nature of the as- synthesized composite. Several rod shaped nanosheets assembled as petals were synthesized with metal particles well-dispersed on their surface. The photocatalytic performance of the nanocatalyst was tested using Rhodamine B (RhB) as the organic pollutant and results revealed that Ag/ ZnO composites have higher photocatalytic efficiency as compared to pure ZnO. ZnO composites also showed enhanced antibacterial property in the zone of inhibition test using Escherichia coli (E.coli) as the bacterial strain. & 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved. Keywords: Ag/ZnO composites; Photocatalytic efficiency; Nanoflowers 1. Introduction Nanotechnology for the past years has emerged as one of the most engrossing and promising areas in the field of research for it covers a wide range of topics from synthesis down to applications of several nanosized particles. Zinc oxide (ZnO), in particular has attracted significant interest from several researchers due to its unique ability of possessing structure- dependent properties, good photocatalytic performance, high oxidative capacity, low cost and ease of availability [1,2]. Also, ZnO has a direct wide band gap of 3.37 eV and large excitation energy of around 60 meV, which make it widely useful in numerous applications in electronics, optics, gas sensing, piezoelectric transducers and photocatalysts. Several synthesis methods like spray pyrolysis, thermal evaporation vapor–liquid–solid (VLS) growth, microemulsion, sol–gel and hydrothermal methods have been carried out to come up with nanostructures that have diverse morphologies since different morphologies present varying unique characteristics [3–6]. Researches showed that the crystallinity and morphology as well as the porosity of the ZnO nanostructures have direct effect on its properties [7,8]. Some of the structures of ZnO that have been successfully synthesized include nanorods [9], nanowires [10], nanoflowers [11] and comb-like and dumbbell structures [12,13]. Among all the synthesized structures the 3D nanostructures, micro/nanoflowers in particular, are believed to be the kind of structures that have the most enhanced proper- ties, especially photocatalytic properties [14]. On the other hand, solution phase techniques are easier and cheaper compared to other methods; however they require longer www.elsevier.com/locate/ceramint http://dx.doi.org/10.1016/j.ceramint.2014.09.126 0272-8842/& 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved. n Corresponding authors at: Department of Bionanosystem Engineering, Graduate School, Chonbuk National University, Jeonju, Jeonbuk 561-756, Republic of Korea. Tel.: þ 82 63 270 4284; fax: þ82 63 270 2460. E-mail addresses: biochan@jbnu.ac.kr (C.H. Park), chskim@jbnu.ac.kr (C.S. Kim). Please cite this article as: M.K. Reyes, et al., Simple and rapid synthesis of mesoporous nanosheet-based ZnO hierarchical structure loaded with metal nanoparticles, Ceramics International (2014), http://dx.doi.org/10.1016/j.ceramint.2014.09.126