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Due to characteristic properties of silver (Ag), Ag nanoparticles have attracted unprecedented attention invarious scientific fields such as sensors, catalysts, antibacterial materials, and so on. To obtain tailor-made functionalities of Ag nanoparticles with desired physicochemical properties, proper fabrication process is needed to control their sizes, morphologies or arrangements by hybridization with different components,immobilization on solid struts, and etc. Herein, we suggest a facile synthetic route to obtain Ag-pillared mesoporous nanoclays through simultaneous crystal growth and arrangement of Ag nanoplates with thehelp of a 2-dimensional inorganic template. To obtain Ag-pillars, layered silver-thiolate self-assemblywas exfoliated to monolayers (Ag precursor) and then in-situ hybridized with layered double hydroxide in a layer-by-layer manner. Through reductive calcination, silver thiolate transformed to Ag-pillars which grew in nanoplate morphology with well-arrangement in confined space of nanoclays. Crystal structure,morphology, and pore structure of Ag-pillars in nanoclays were systematically characterized. Surface enhanced Raman scattering effect of arranged Ag-pillars on metal oxide substrate obtained upon calcination was also investigated with rhodamine 6 G. Refereed/Peer-reviewed

Silver metal nanostructures have gained much interest, due to their utility in various fields, based on their unique properties at nanosize. Tremendous research efforts have been made to establish synthetic methods to manipulate their shape and size. The most challenging synthesis in silver nanostructures has been known as a plate-like shape having a few nanometers size thickness and high aspect ratio. Here, we demonstrate a novel and facile synthetic route for ultrathin (≤1 nm) silver nanosheets using silver carboxylthiolate as precursor. Such silver thiolate formed single-layered colloid in aqueous basic solution, due to the electrostatic repulsion between carboxylate groups. These single layers of silver thiolates were stabilized within the interlayer space of layered double hydroxide (LDH). When silver thiolates confined in LDHs were calcined under reductive atmosphere, the LDHs effectively suppressed the vertical growth of silver crystals. Refereed/Peer-reviewed

Nanocomposites containing magnetic iron oxide (magnetite) nanoparticles and layered double hydroxide (LDH) nanosheets were prepared by two different methods, exfoliation-reassembly and coprecipitation, for aqueous chromate adsorbent. According to X-ray diffraction, scanning electron microscopy, and atomic force microscopy, both nanocomposites were determined to develop different nanostructures; LDH nanosheets well covered magnetite nanoparticles with house-of-cards-like structure in exfoliation-reassembly method, while coprecipitation resulted in LDH particle formation along with magnetite nanoparticles. Zeta-potential measurement also revealed that the magnetite surface was effectively covered by LDH moiety in exfoliation-reassembly compared with coprecipitation. Time, pH, concentration dependent chromate adsorption tests, and magnetic separation experiments exhibited that both nanocomposites effectively adsorb and easily collect chromate. However, exfoliation-reassembly nanocomposite was determined to be slightly effective in chromate removal by 10%. Chromate adsorbed nanocomposites could be regenerated by treating with bicarbonate and the regenerated nanocomposites preserved 80% of chromate adsorption efficacy after three times of recycling. Refereed/Peer-reviewed