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Cubic-phase cadmium sulfide (CdS) nanoparticles were formulated through dropwise precipitation. XRD analysis shows that the CdS has an average nanocrystallite size of approximately 3.36 nm. FTIR results reveals that a strong band appeared around 600 cm-1 is due to Cd-S bonds. SEM image demonstrates that many tiny spherical nanoparticles are homogeneously distributed on the sample surface. The CdS nanoparticles show a prominent UV-Vis absorption peak at 506 nm with a direct band gap of 2.24 eV. CdS nanoparticles has induced remarkable photobleaching effect on the highly stable R6G dye solution under UV illumination, which is applicable for future wastewater treatment. [ABSTRACT FROM AUTHOR]

In this work, an optothermal wave characterization based on the photoacoustic (PA) technique was first implemented to investigate the thermal and carrier transport properties of Au thin film layer deposited on Si wafers (Au/Si) annealed at different temperatures. The XRD pattern showed that a metastable gold (Au) silicide of Au81Si19 phase formation was traced at annealing temperature of 330 oC and this structure disappeared when the temperature was further elevated up to 370 oC. The result showed that the PA signal obtained for Au/Si structure was lower than the pure Si wafer. The thermal and carrier transport properties of Si and Au/Si were elucidated from the fitting of PA signalphase relation. From the result, the thermal diffusivity and surface recombination velocity of Au/Si increased with shorter recombination lifetime as the raise of annealing temperature. Nonetheless, as the temperature approaches 370 °C, the surface recombination and thermal transport process diminishes, which may be ascribed to the rupture of silicide clusters. [ABSTRACT FROM AUTHOR]

In the present work, for the first time, a homogeneous sponge-like porous CuO nanostructure was successfully developed via an eco-friendly precipitation route. The product was obtained using copper (II) nitrate hemi(pentahydrate) and NaOH as reactants without thermal treatment or use of any additives and surfactants. The crystallographic structure, functional group and surface morphology of the samples were characterized by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). XRD analysis reveals the formation of a pure and highly crystalline CuO monoclinic structure with an average grain size of around 23.8 nm. Besides, the FTIR result indicates that the characteristic vibrational bands appeared in the 400-650 cm–1 range can be ascribed to the stretching vibration of the Cu–O bond. Moreover, SEM images of the CuO sample clearly demonstrate a uniform sponge-like nanoporous structure with fiber growth on the surface with pore sizes ranging from 70 to 90 nm. Hence, this fascinating structure could potentially serve as a catalyst for the destruction of pollutants as well as a solar absorber for capturing sunlight energy. [ABSTRACT FROM AUTHOR]

The wet etching of silicon surfaces by the use of acidic or fluoride solutions is of both technological and fundamental significance, which is essentially to be applied to produce a reliable silicon chip at desired thickness for microelectronic packaging. In this work, we have investigated the wet etching effect on thickness dissipation, weight loss, etching rate, surface morphology and crystalline nature of Si wafer immersed in the 48 % HF/water solution. The etch rate was ascertained from the variation of weight loss and depth etched against time. The results show that the thickness reduction and weight loss of silicon increases as the etching time increases. Roughened surface is observed on the etched Si wafer surface under the high-resolution optical microscope. From the XRD analysis, it shows that the crystalline peak intensity of silicon becomes weaker after etching, implying the reduced light scattering from the formed amorphous structure surface on the Si substrate. After all, this finding can be valuably referred to produce a reliable Si thin wafer, which is crucial in thinner microelectronic devices fabrication and nanopackaging, and in turn reduces environmental pollution and energy consumption for future sustainability. [ABSTRACT FROM AUTHOR]

In this work, room-temperature treated CdS nanoparticles were prepared in KOH solution via precipitation at different pH values by varying the ammonium nitrate (NH4NO3) concentration. The crystallite phase and size, surface morphology and infrared frequencies of functional groups were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The SEM images show that the CdS nanoparticles are spherical in shape. Meanwhile, the FTIR result reveals that a broad band occurred in the range of 400-700 cm−1 could be attributed to the molecular bonding structure of CdS. The XRD patterns exhibit four well-resolved crystalline peaks that represents the diffraction planes of a cubic CdS phase. Nevertheless, a minor decrement in the intensity for both infrared and crystalline bands denotes a slight reduction in structure crystallinity and further indicates that a higher purity of finer CdS nanoparticles is obtained as the pH value decreases. Also, the diffraction peak becomes slightly widen that implies a decrease in the mean crystallite size as validated by Debye-Scherrer method. Owing to their unique nanostructural and morphological features, the CdS nanoparticles obtained in this study have potential applications in photonic devices, optoelectronics, photocatalysis and solar cells. [ABSTRACT FROM AUTHOR]

Graphene nanoplatelets (GNP) are just one of the attractive graphene-based nanomaterials that are rapidly emerging and have sparked the interest of many industries. These small stacks of platelet-shaped graphene sheets have a unique size and morphology that quickly disperse into other materials such as polymers, resulting in higher-value composite materials with improved thermal, conductivity, and mechanical capabilities. A detailed analysis of reinforced High-Density Polyethylene (HDPE) using different sizes (2, 15, 25 μm) and compositions (8, 10, 15 wt.%) of Graphene Nanoplatelets (GNP) has been conducted. The microstructure of the HDPE/GNP nanocomposites was extensively examined during the melt blending and injection moulding processes. Based on the results, the nanocomposites with different sizes of GNP exhibited dissimilar behaviour with different compositions. Furthermore, scanning electron microscope (SEM) results indicated a homogeneous dispersion for GNP in melt mixing. Moreover, thermogravimetric (TG) data demonstrate that increasing filler showed a slight increase in the material's thermal stability. The use of GNP improved mechanical properties, as evidenced by the increases in Young's modulus of yield strength from around 100 MPa to over 400 MPa. This study provides a practical reference for the industrial preparation of polymer-based graphene nanocomposites. [ABSTRACT FROM AUTHOR]