Mesoporous SiO2 was prepared from rice husk for removal of methylene blue (MB) from aqueous solution. Asprepared SiO2 was characterized by FE-SEM, TEM, XRD, FT-IR and N2 adsorption/desorption isotherm. The effects of SiO2 dosage and contact time on adsorption of dye were investigated. The optimal dosage of SiO2 for removing methylene blue was 0.05 g and the removal efficiency of methylene blue reached to 91.9 % after 50 min of adsorption. The adsorption kinetic of methylene blue was studied to understand the mechanism of adsorption process. The kinetic data was analyzed by pseudo-first-order, pseudo-second-order, and intra-particle diffusion models. The results showed that rate of adsorption dye followed pseudo-second-model with a good regression correlation (R 2 = 0.999), the value of rate constant for adsorption process was calculated as 0.017 (g.mg -1 .min -1 ) and film diffusion was the rate limiting step. In addition, the cyclic test for as-prepared SiO2 was investigated and the removal efficiency was remained at 80.2% at 3 rd cyclic experiment.

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Light extraction efficiency of GaN-based light emitting diodes were significantly enhanced using silver nanostructures incorporated in periodic micro-hole patterned multi quantum wells (MQWs). Our results show an enhancement of 60% in the wall-plug efficiency at an injection current of 100 mA when Ag nano-particles were deposited on side facet of MQWs passivated with SiO2. This improvement can be attributed to an increase in the spontaneous emission rate through resonance coupling between localized surface plasmons in Ag nano-particles and the excitons in MQWs.

Crystalline structure and optoelectrical properties of silver-doped tin monoxide thin films with different dopant concentrations prepared by DC magnetron sputtering are investigated. The X-ray diffraction patterns reveal that the tetragonal SnO phase exhibits preferred orientations along (101) and (110) planes. Our results indicate that replacing Sn 2+ in the SnO lattice with Ag + ions produces smaller-sized crystallites, which may lead to enhanced carrier scattering at grain boundaries. This causes a deterioration in the carrier mobility, even though the carrier concentration improves by two orders of magnitude due to doping. In addition, the Agdoped SnO thin films show a p-type semiconductor behavior, with a direct optical gap and decreasing transmittance with increasing Ag dopant concentration.

Nowadays, Fused Deposition Modeling (FDM) has accomplished huge proficiency in modelling and wide variety in products shape and size in the industry. Alongside with its development, many problems came up, one of which is to ensure the technical requirements of the parts such as: compressive strength, tensile strength, dimensional accuracy, etc. To solve this problem, new composite materials has been developing and at the same time correlative process parameters has been optimized to achieve the most optimal technical requirements of that material. In this paper, we focus on researching the effect of process parameters consist of: raster angle; build direction and layer thickness on the part’s compressive strength made by one of the newest composite material which is the PLA-Copper filament. Central composite design (CCD) methodology is used to lower the experimental runs, the analysis of variance (ANOVA) method is employed to investigate the process parameters in order to achieve optimal compressive strength.

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We found that inserting silver nanoparticles (AgNPs) between two layers of reduced grapheme oxide (rGO) has an effect on tailoring the work function of rGO. The utilization of rGO/AgNPs/rGO sandwich structure as the hole extraction layer in polymer solar cells is demonstrated. Solution-processable fabrication of this sandwich structure at the ITO/active layer interface facilitates the extraction of hole from active layer into ITO anode because of lowering the barrier level alignment at the interface. It results in an improvement of the short circuit current density and the overall photovoltaic performance.

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