Electrochemical behaviour of spin-coated films of vanadium pentoxide xerogel in aqueous electrolyte. Electron transfer between vanadium centres in the gel layers and intercalated tris (2,2′-bipyridyl) metal cations

Characterization of Supported Solid Thin Films of Laponite Clay. Intercalation of Rhodamine 6G Laser Dye

“…[49][50][51] Under these conditions, an average thickness of around 150 nm was estimated for Lap film by the gravimetric method considering the film weight, the plate area, and the clay density. 47 This average film thickness agrees with those values obtained from the AFM profiles showing the depth of the groove performed in the Lap film (Figure 3, left): 250 and 120 nm in the center and in the edge of the substrate, respectively. This thickness was checked to be reproducible for several independent experiments when the clay suspension and the spinning conditions were perfectly established.…”

“…From our experience, the best Lap thin films were obtained for a 2 g L -1 clay aqueous suspension aging during at least 1 week to get stable and viscous gels, , in two spinning steps: first spinning at low rotation speed (500 rpm) during 30 s to spread the clay particles over the plate area and a second step with higher rotational conditions (2500 rpm) for 45 s to properly obtain the supported film. These spinning conditions are similar to those proposed by other authors. − Under these conditions, an average thickness of around 150 nm was estimated for Lap film by the gravimetric method considering the film weight, the plate area, and the clay density . This average film thickness agrees with those values obtained from the AFM profiles showing the depth of the groove performed in the Lap film (Figure , left): 250 and 120 nm in the center and in the edge of the substrate, respectively.…”

“…All the films were dried overnight at 35 °C in an airflow oven. The average thickness of Lap thin films was estimated by a gravimetric method, 47 considering the weight of the deposed clay, the plate area, and the density of the clay (estimated to be around 2 g L -1 for Lap clay from the weight and the volume of its crystallographic cell). 44 This average thickness was also confirmed by AFM images.…”

Dispersion of Organic Dyes in n-Hexadecylamine-Intercalated Vanadium Xerogel Thin Films

“…The peaks were broadened in the sample with a nominal C16=VXG ratio of 0.55 and a new, small peak at 310 nm appeared. It has been reported that the peak at 373 nm disappeared upon electrochemical reduction [40][41][42][43]. When the nominal C16=VXG ratio was greater than 1.1, a similar spectrum was obtained containing two peaks at 305 and 230 nm, suggesting perturbation in V¼O by the introduction of C16 when the C16=VXG ratio was 0.4 to 1.…”