01769nas a2200205   4500008004100000022001400041245011600055210006900171260006500240300000800305490000700313520097500320653002301295653002001318653000901338653001501347100003701362700003601399856012801435       2016                        eng d  a1420-304900aGold incorporated mesoporous silica thin film model surface as a robust SERS and catalytically active substrate0 aGold incorporated mesoporous silica thin film model surface as a  aST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLANDbMDPI AGcMAY  a6670 v213 a<p>Ultra-small gold nanoparticles incorporated in mesoporous silica thin films with accessible pore channels perpendicular to the substrate are prepared by a modified sol-gel method. The simple and easy spin coating technique is applied here to make homogeneous thin films. The surface characterization using FESEM shows crack-free films with a perpendicular pore arrangement. The applicability of these thin films as catalysts as well as a robust SERS active substrate for model catalysis study is tested. Compared to bare silica film our gold incorporated silica, GSM-23F gave an enhancement factor of 10(3) for RhB with a laser source 633 nm. The reduction reaction of p-nitrophenol with sodium borohydride from our thin films shows a decrease in peak intensity corresponding to -NO2 group as time proceeds, confirming the catalytic activity. Such model surfaces can potentially bridge the material gap between a real catalytic system and surface science studies.</p>10agold nanoparticles10amodel catalysis10aSERS10aThin films1 aSekhar, Anandakumari, Chandrasek1 aVinod, Chathakudath, Prabhakara  uhttp://library.ncl.res.in/content/gold-incorporated-mesoporous-silica-thin-film-model-surface-robust-sers-and-catalytically02015nas a2200253   4500008004100000022001400041245019700055210006900252260000800321300001100329490000800340520110300348653001801451653001901469653001201488653000901500653002501509653001601534100001301550700002001563700002001583700003101603856012701634       2020                        eng d  a0921-510700aTemperature assisted reorganization of silver nanoparticles in free-standing, flexible chitosan functionalized reduced graphene oxide thick films: A potential SERS probe for folic acid sensing0 aTemperature assisted reorganization of silver nanoparticles in f  cFEB  a1144540 v2523 a<p>Chitosan and silver functionalized free standing reduced graphene oxide (rGO) films were prepared using simple soak and dry strategy. Redistribution of silver aggregates on chitosan functionalized rGO films were observed by thermally annealing these films at 450 degrees C, in an inert atmosphere. The re-organization / redistribution of silver aggregates in the rGO films were studied using in-situ Raman scattering signals. The redistribution of silver particles occurs through melting of micron sized silver aggregates during annealing. The rearrangement of the micro-sized silver aggregates to spherical silver nanoparticle on chitosan functionalized rGO film, as a result of temperature was assisted through factors such as graphene surface ripple rearrangement and the denaturation of rGO surface interacting chitosan chains. These free-standing films with redistributed silver nanoparticles showed excellent surface enhanced Raman scattering (SERS) effect with enhanced Raman signals for folic acid sensing, showcasing its potentiality to be utilized as flexible SERS based sensors.</p>
10aFree-standing10agraphene oxide10asensing10aSERS10asilver nanoparticles10aThick-films1 aAsha, S.1 aAnanth, Nimrodh1 aJose, Sujin, P.1 aRajan, Michael, Anjello Jo  uhttp://library.ncl.res.in/content/temperature-assisted-reorganization-silver-nanoparticles-free-standing-flexible-chitosan