title: Caulerpa racemosa: a marine green alga for eco-friendly synthesis of silver nanoparticles and its catalytic degradation of methylene blue.
abstract: In this study, a simple and green method has been demonstrated for the synthesis of highly stable silver nanoparticles (AgNPs) using aqueous extract of Caulerpa racemosa (C. racemosa) as a reducing and capping agent. The formation and stability of AgNPs were studied using visual observation and UV-Visible (UV-Vis) spectroscopy. The stable AgNPs were further characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and high resolution transmission electron microscopy (HR-TEM) with energy dispersive spectroscopic (EDS) methods. The biosynthesized AgNPs showed a sharp surface plasmon resonance peak at 441 nm in the visible region and they have extended stability which has been confirmed by the UV-Vis spectroscopic results. XRD result revealed the crystalline nature of synthesized AgNPs and they are mainly oriented in (111) plane. FT-IR studies proved that the phytoconstituents of C. racemosa protect the AgNPs from aggregation and also which are responsible for the high stability. The size of synthesized AgNPs was approximately 25 nm with distorted spherical shape, identified from the HR-TEM images. The synthesized AgNPs showed excellent catalytic activity towards degradation of methylene blue.
authors.affiliation: School of Chemical Engineering, Yeungnam University, Gyeongsan, 712-749, Republic of Korea.
authors.forename: Thomas Nesakumar Jebakumar Immanuel
authors.initials: TN
authors.lastname: Edison
authors.affiliation: School of Chemical Engineering, Yeungnam University, Gyeongsan, 712-749, Republic of Korea.
authors.forename: Raji
authors.initials: R
authors.lastname: Atchudan
authors.affiliation: Department of Chemistry, VSA Group of Institutions, Salem, 636010, Tamil Nadu, India. kamal.kathir123@gmail.com.
authors.forename: Chennappan
authors.initials: C
authors.lastname: Kamal
authors.affiliation: School of Chemical Engineering, Yeungnam University, Gyeongsan, 712-749, Republic of Korea. yrlee@yu.ac.kr.
authors.forename: Yong Rok
authors.initials: YR
authors.lastname: Lee
mesh_terms: D002384:Catalysis; D046068:Caulerpa / Q000378:metabolism*; D006868:Hydrolysis; D053768:Metal Nanoparticles / Q000737:chemistry*; D008751:Methylene Blue / Q000378:metabolism*; D046529:Microscopy, Electron, Transmission; D012834:Silver / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D014961:X-Ray Diffraction
chemical_list: D012834:Silver; D008751:Methylene Blue
keywords: Catalyst; Caulerpa racemosa; HR-TEM; Marine alga; Silver nanoparticles