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The electrical and optical properties of nanomaterials depend on their structural form. As an effort to develop an advanced nanomaterial, zinc oxide (ZnO) is interesting to synthesis for many applications such as active material for solar cells and biosensors. This paper provides the role of palladium and plasmonic materials in growing ZnO nanostructure, with a focus on its structural analysis. Nanomaterial ZnO was grown by seed-mediated hydrothermal method with layering by plasmonic materials, i.e. gold (Au) and platinum (Ag). X-ray diffraction analysis shows the presence of three dominant peak angles, i.e 34.43o, 36.32o, and 47.49o corresponding to crystal orientation of (002), (101) and (102), respectively. Palladium (Pd) treatment plus layering by plasmonic materials give a higher size of the nanostructure, but their electric band gaps are decreasing slightly. These findings also supported by high absorbance in UV-vis spectra. Gold layering on the nanomaterial gives a more significant role than platinum which indicated by higher size in diameter and higher absorption of UV-Vis spectra. The average size of pristine ZnO, ZnO:Pd, ZnO:Pd:Ag, and ZnO:Pd:Ag are 44.13, 45.99, 45.28, and 44.81 nm, respectively.

Charge-transfer and photoactivity at an interface of a photoactive materials, such as ZnO, is critically influence the performance of dye-sensitized solar cell (DSSCs). The performance of DSSCs utilizing Au decorated ZnO nanorod photoanode with Au nanoparticles grown at seven different growth times from 0.12 up to 6 min were studied. It was found that the charge transfer characteristic of DSSCs devices utilizing Au decorated ZnO nanorods increased with the increasing of Au nanoparticles size and density and optimum at Au nanoparticles size of ca. 15 nm and density of approximately 4–10 nanoparticles/nanorods. At this condition, the charge transfer resistance as low as 7.4 Ω was recorded. This is equivalent to power conversion efficiency of 1.11%. The charge transfer resistance gradually declined when the growth time further elongated. The efficient charge transfer can be associated to the excellent catalytic properties of Au nanoparticles on ZnO nanorods. This also improves its carrier transport in the device as judged from significantly low dark current properties. The improvement of light absorption can also be considered to improve the performance, attributed to the surface plasmon resonance (SPR) effect of the gold nanoparticles. The preparation of Au nanoparticles decorated ZnO nanorods and the mechanism of charge transfer characteristics will be discussed.

Ternary cobalt-based metal oxide (ZnCo2O4) has been successfully coated onto aluminum substrate via sol–gel method. The coatings were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and UV–Vis–NIR spectrophotometry. Thermal degradation of the coatings was probed by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Model of crystal growth kinetics and density functional theory (DFT) calculations further probed the crystalline structure evolution. The predicted ZnCo2O4 crystalline structures were confirmed by XRD and EDX. The grain growth kinetic model for ZnCo2O4, derived from Lifshitz–Slyozov–Wagner (LSW) theory, determined that the growth of crystalline phases is unaffected by the annealing temperature; however, the crystallites’ sizes decreased with the increase in precursor concentration. DFT analysis indicated that structural energy stability between the bulk state and slabs of ZnCo2O4 was at two oxygen layers (O-layers) with an optimum grain width of 17.21 A. Interestingly, the morphology of ZnCo2O4 represented a rose-like template structure formed by inter-connecting layers of nanosheets. This unique surface morphology enhanced the optical absorptance properties up to α = 70.7%.

The addition of metal dopant into ZnO nanocrystals may induce changes both electronic and crystal grow properties, which later modify its photoactivity and surface physico-chemistry properties, improving its photovoltaic performance in DSSCs application. Here we report a dramatic distortion in the crystal grow orientation of ZnO in the presence of ruthenium ion dopant, changing the crystal morphology from fine hexagonal shape nanorod to starfruit-like shape nanorod. We found that such modification in the ZnO nanostructure enhanced photovoltaic properties, in typical case increased up to two times increment to 0.43%, compared to pristine hexagonal nanorod sample (0.2%). The present results may provide alternative strategy to augment the photoactivity of the nanostructure. High performance DSSC device will then be obtained when optimized fabrication procedure is implemented.

Dye sensitized solar cell (DSSC) is made with a layer arrangement of fluorine tin oxide (FTO), zinc oxide (ZnO), dye, electrolyte, and plastisol. ZnO nanorods which play a role as photoanode in DSSC have been successfully grown on FTO substrate using seed mediated hydrothermal method at temperature of 90 oC for 8 hours. Modification was made to increases the efficiency of DSSC by adding silver (Ag) with concentration of 5 mM into dye molecules. ZnO characterization was performed using ultra violet-vissible (UV-Vis) spectroscopy and field emission scanning electron microscopy (FESEM). The strongest UV-Vis absorbance spectrum with the optimum absorbance for the ZnO sampel was occurred at the wavelength range of 300 – 360 nm. Meanwhile, for the ZnO sample with addition of 5 mM Ag into dye molecule was occurred at the wavelength range of 440 – 530 nm. FESEM image of the sample shows the as-synthesized ZnO nanorods have hexagonal cross section. I-V characteristics in the light mode was carried out to determine the efficiency of DSSC using a halogen lamp with an intensity of 100 mW/cm 2 . The efficiency of DSSC using ZnO with addition of 5 mM Ag into dye molecule is 0.462%, increases compared to the efficiency of DSSC using ZnO without addition of Ag into dye molecule which only produce 0.45% efficiency. These results indicate that the addition of Ag can increase the efficiency of DSSC.

This paper reports the effect of hexamethylenetetramine (HMT) concentration on the structural, morphological and optical properties of B-doped ZnO nanotubes arrays. B-doped ZnO nanotubes were employed as anode in dye-sensitized solar cells (DSSCs). The effect of these properties on the photovoltaic performance was also studied. B-doped ZnO nanotube arrays were prepared via hydrothermal technique on FTO substrate at constant concentration of zinc nitrate. The field emission scanning electron microscopy (FESEM) images indicate that the density and length of B-doped ZnO nanotubes increase with the concentration of HMT. However, the diameter decreases with the increase of HMT concentration. The JSC, VOC, FF and η of 1.48 mA cm−2, 0.38 V, 0.39 and 0.224% respectively have been obtained by the DSSC utilizing B-doped ZnO nanotube prepared at 0.06 M HMT.

An elegant technique of synthesizing semiconductor lead sulfide nanoparticles (PbS-NPS) embedded in Langmuir-Blodgett (LB) films is presented here. Stearic acids have been used as a matrix to form and grow the quantum-sized PbS. Pure Y-type Pb-salts of stearic acid (SA) LB films were prepared at a dipping speed of 15 mm/min and surface pressure of 28 mN/m. PbS-NPs were formed inside LB films of SA by exposure the LB films to hydrogen sulfide (H2S) gas. The preparation of PbS-NPs is discussed in terms of particle formation and growth. The presence of PbS-NPs was investigated by UV-visible absorption. It was found that the PbS-NPs within SA LB films indicated a large blue shift of the optical absorption edge. The estimation of the size distribution performed by optical measurements allows one to attribute the particle range a few nanometers. This figure seems to depend upon the reaction conditions as well as the quality of the initial LB films.

Synthesis parameter plays important role in modifying physical property of metal oxide films which serve as photoanode in dye-sensitized solar cell (DSSC). This paper reports the synthesis of boron doped ZnO nanostructures via seed mediated growth hydrothermal technique and their application as photanode in DSSC. The growth process was carried out at various solution concentrations, 0.1, 0.2, 0.3 and 0.4 M. The solution contains 1 % wt. dimethyl borate as boron source, hexamethylenetetramine (HMT) surfactant and zinc nitrate (Zn(NO3)2). The samples are crystalline with wurtzite phase. The morphological shape of the samples changes with the growth solution concentration. The optical absorption increases as the concentration increases. However, the band gap does not significantly change with the concentration. The DSSC utilizing the ZnO sample prepared at 0.1 M solution performs the best photovoltaic parameters with the JSC of 0.969 mA cm-2, FF of 0.48 and η of 0.222%, respectively since it shows the highest absorption and lowest photoluminescence in visible region.

This paper reports the synthesis of ZnO nanorods via seed-mediated growth hydrothermal technique and their application in dye-sensitized solar cells (DSSCs). The growth process was carried out at various temperatures, namely 60, 70, 80, and 90 °C for 8 h at 0.1 M zinc acetate dehydrate (ZAD) to investigate the effect of growth temperature on the property of ZnO sample and on the performance of the DSSC-containing ZnO sample. The growth process was also carried out at various growth times, namely 2, 4, 6, and 8 h at 90 °C at 0.1 M ZAD to investigate the effect of growth time on the property of ZnO sample and on the performance of the DSSC. It was found that the morphology of ZnO nanorods in terms of grain size and length increases with the growth temperature. The peak intensity of XRD patterns, crystallite size, optical absorption, and photocurrent also increase with the growth temperature. The optical absorption and power conversion efficiency (η) increase as the growth time increases. The DSSC utilizing the ZnO nanorods synthesized at 90 °C for 8 h demonstrates the J SC, V OC, FF and η of 1.860 mA cm−2, 0.52 V, 0.287, and 0.277 %, respectively.

ZnO material coated with Cu + Ag was successfully grown using seed mediated hydrothermal method at a temperature of 90° C for 8 hours with a variation of concentration of Ag, 10 mM, and 20 mM. The growth of ZnO nanomaterials was carried out on the FTO substrate (Flourine Tin Oxide). The Samples were characterized using, Field Emission Scanning Microscope (FESEM), and X-ray Diffraction (XRD). The FESEM photos show ZnOnanorod coated with Cu + Ag have grown on FTO having a nanoflower shape that consructed from ZnOnanorods with their orientation . The XRD pattern shows five peaks at 2θ: 31.69 °; 34.36 °; 36,18 °; 47.52 °; and 56.4 °. Based on the results of the analysis of the OriginPro 8 program each peak in a row according to the crystal orientation (100), (002), (101), (012), and (110). The stongest line was found in the crystal plane (101). DSSC was fabricated using ZnO nanomaterial coated with Cu + Ag as active material, N719 dye, liquid electrolyte, and plastisol as catalyst on the counter electrode. The results of I-V measurements at halogen lamp with ilumination its intensity of 100 mW/cm2 of the cells has producedthe highest efficiency value based on Cu coated ZnO was based DSSC 0,98% with a Cu concentration of20mM.These results show that the addition of Cu layer can increase the efficiency of DSSC based on ZnO by 123% compared to ZnO without Cu based DSSC. Addition of Ag to active material of Cu coated ZnO nanomaterial did not have a positive effect on the efficiency of DSSC cells.

ZnO nanorods have successfully been grown on the surface of FTO. The growth of ZnO nanorods was carried out using the seed-mediated growth method, whereas the Ni doping was carried at different concentrations. The effect of nickel doping on ZnO nanorods was observed using field emission scanning electron microscope (FESEM), UV-Vis spectroscopy, and X rays diffraction (XRD). ZnO nanorods having hexagonal shape were shown by FESEM images, and overlap of ZnOnanorods forming a nanoflowers with wider rod size. UV-Vis spectra showed that strong absorption occurred at a wavelength of 390-300 nm, the highest intensity of absorption was resulted by 15mM sample. The energy gap of the sample decreased as increasing its concentration. XRD pattern of the samples showed the diffraction peaks occurred at angles of 2θ = 31.72°, 34.45°, 36.20°, 47.50°, and 56.57° that represented the crystal plane orientation of (100), (002), (101), (102), and (110).

A directional fiber coupler has been successfully fabricated by using fusion and elongation methods. Two or more single mode fibers (SMFs) were joined by injecting H 2 gas at 1 bar and heating the coupling region while they are pulled for various pulling speeds. Coupling mode theory (CMT) in form of transfer matrix was involved to determine the transfer power propagation between fibers. However, coupling coefficient has been derived by using Henkel and Bessel function and assuming that cores of fibers are only touching each other. The periodical propagation of power transfer depends on the coupling coefficient and the coupling length. The increment of coupling coefficient has been exhibited as function of the separation distance between fibers axes and the degree of fusion. The coupling coefficient is also proportional with the increasing the degree of fusion. Good performance of the fiber couplers have been produced with typical of exertion loss is about 0.03 dB by pulling the coupling region at 1300 °C with the pulling speed of 150 μm/s.

This paper reports the synthesis of gallium doped ZnO nanostructures via seed mediated growth hydrothermal technique and their application as photo-anode in DSSC. ZnO nanostructures have been grown on Flourin Tin Oxide (FTO). The precursor used in this research was zinc-nitrate-hexahydrate (Zn (NO3)2.6H2O) and hexa-metylene-tetramine (HMT) was chosen as surfactant. The growth process was carried out at various precursor solution concentrations, 0.1, 0.2, 0.3 and 0.4 M at 90°C for 8 hours. The growth solution was then doped with 1% wt gallium nitrate hydrate. The grown ZnO nanostructures were characterized by X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-Ray (EDX) and UV-Vis Spectroscopy. The samples were crystalline with wurtzite-hexagonal and their crystal orientation was (100), (002), (101), and (110). The morphological shape of the samples changed with the concentration of the precursor. The optical absorption decreased as the concentration increas...

ZnO nanostructures coated Cu (Copper) have been successfully grown using a method of seed mediated hydrotermal. The growth of Cu coated ZnO nanostructures were used as an active material of DSSC. The Cu on ZnO nanostructures has been coated at a concentration of 10 mM at room temperature in 30 minutes. The samples were characterized using Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray (EDX). The FESEM images showed that the geometrical shape of ZnO nanostructures was nanoflower. Spectra of EDX showed Cu was really exist in all samplesof about 0.8%. A DSSC was fabricated by using the ZnO nanostructured coated Cu as an active material.The results of I-V measurements under iluminattion of halogen lamp its intensity of 100 mW/cm2 has produced efficiency 0.35% (DSSC without copper) and increasedto 0,43% whenCuwas coated on ZnO.

Activated carbon (AC) from Terminalia catappa fruit shells has been produced through microwave irradiation assisted chemical activation. Potassium hydroxide (KOH) was used as activating agent with ratio of mass percentage of pre-carbonized of Terminalia catappa fruit shells and KOH of 2:1. The AC was irradiated using microwave with the output power of 630 Watt and different irradiation time of 15, 20, and 25 minutes. The physical properties of ACs i.e. microstructures, surface morphology, and BET surface area were characterized using X-ray diffraction, scanning electron microscopy, and N2 adsorption/desorption isotherm, respectively. Interlayer spacing d002 and d100, and stack width La increased, and stack height Lc decreased with increasing irradiation time. The N2 adsorption/desorption isotherm data of the ACs showed the BET surface area of 365 and 300 m2/g for AC15 and AC25, respectively.

Magnetite nanoparticles (Fe3O4) are a type of magnetic particle with huge potential for application as a drug carrier due to their excellent superparamagnetic, biocompatible, and easily modified surface properties. One characteristic of nanoparticles is that they can be controlled by studying the evolution of crystal growth. The purpose of this research is to study the evolution of magnetite-crystal growth and determine the crystal growth kinetics using the Ostwald ripening model. Magnetite nanoparticles were synthesized from FeCl3, citrate, urea, and polyethylene glycol using the hydrothermal method at 220oC for times ranging from 1–12 hours. The characterizations using X-ray diffraction (XRD) indicated that the magnetite began to form after 3 hours synthesis. The crystallinity and crystal size of the magnetite increased with the reaction time. The diameter size of the magnetite crystals was in the range of 10–29 nm. The characterizations using a transmission electron microscope (TEM) showed that magnetite nanoparticles had a relatively uniform size and were not agglomerated. The core-shell nanoparticles were obtained after 3 hours synthesis and had a diameter of 60 nm, whereas the irregular-shaped nanoparticles were obtained in 12 hours and had a diameter of 50 nm. The characterizations using a vibrating sample magnetometer (VSM) revealed that magnetite nanoparticles have superparamagnetic properties. The magnetization saturation (Ms) value was proportional to the degree of crystallinity. The magnetite-crystal growth data can be fitted to an Ostwald ripening model with the growth controlled by the dissolution of the surface reaction (n?4).

Binderless activated carbon monoliths (ACMs) for supercapacitor electrodes were prepared from sugarcane bagasse by two different methods of physical and combination of physical-chemical activation process. The CO2 gas was used as physical activation agent and 0.3 M KOH was chosen as chemical activation agent. The ACMs were tested as electrodes in two-electrode systems of the coin tape cell supercapacitor that consists of stainless steel as current collectors and 1 M H2SO4 as an electrolyte. The improving of resistive, capacitive and energy properties of combination of physical-chemical ACMs electrodes were shown by an impedance spectroscopy, a cyclic voltammetry and a galvanostatic charge-discharge method. The improving of resistive, capacitive and energy properties as high as 1 to 0.6 Ω, 146 to 178 F g-1, 3.83 to 4.72 W h kg-1, respectively. The X-ray diffraction analysis and field emission scanning electron microscope were performed to characterize the crystallite and morphology characteristics. The results showed that the combination of physical-chemical activation process have given a good improving in performance of the bagasse based ACMs electrodes in supercapacitor application.

Various eggs shell membranes (ESMs) have been used as a separator for supercapacitor application. The separator was prepared from different membranes such as chicken eggs shell membrane (CESM), duck eggs shell membrane (DESM) and goose eggs shell membrane (GESM). The ESMs were tested as a separator in a two-electrode system, the sandwich-type supercapacitor cell consists of two activated carbon monoliths as electrodes, two stainless steel as current collectors and 1 M H2SO4 solution as an electrolyte. The electrochemical performance of the ESMs was characterized by an electrochemical impedance spectroscopy, a cyclic voltammetry and a galvanostatic charge-discharge. The results of this study exhibit all of the ESMs as a good candidate for supercapacitor separator. However, the CESM was shown excellence electrochemical properties, such as low resistance, high energy density and power density. The scanning electron microscope (SEM) micrograph and X-ray diffraction analysis were also proved that the ESMs are a promising low-cost separator for supercapacitor application.

We provide a preliminary study of ZnO nanostructure synthesis by coating aluminium and metallic plasmonic Au-Ag using seed mediated hydrothermal method. The growth process is carried out on the FTO substrate and characterized using UV-Vis, XRD, FESEM and EDX spectrophotometer system. The UV-Vis spectrum shows that strong absorption occurs at wavelengths around 370 nm, for all samples. The XRD pattern shows three diffraction peaks at angles 2θ = 34.43°, 36.32° and 47.49°. Each peak corresponds to the crystal fields of (100), (002) and (101). Morphology of the samples shows the presence of ZnO nanorod. A compact and denser nanostructure also obtained.

Magnetite (Fe3O4) nanoparticles becomes a new innovation that gets attention of biomedicine scientists. Magnetite can be applied to cancer treatment as a drug carrier because it’s good biocompatibility and very low toxicity. The purpose of this study was to determine the effect of temperature and stirring rate on the magnetite particle characteristics prepared by co-precipitation method. Firstly, FeCl3 and FeCl2 with 2:1 mole ratio were reacted with 10% NH4OH at 40 - 80°C temperatures and stirring speed of 300 - 500 rpm in a beaker glass. Subsequently, the precipitate was separated using filter paper and it dried into air oven at 100°C. The properties of obtained magnetite powder were determined using XRD and SEM. From XRD pattern indicates that magnetite formed at all temperatures with crystallite diameter in the range of 10-12 nm. The SEM results indicate the agglomeration of the magnetite particles with size in the range of 2.7 to 3.3 μm. In the other hand, the higher of temperature and stirring rate of agitation will make the agglomeration of the particles become more uniform. The increasing of temperature and the stirring rate will increase the magnetite crystallinity level.

A simple technique of seed-mediated growth has successfully been performed to grow gold nanoplates onto solid substrates. The growth of gold nanoplates have been carried out attemperature of 28-30°C in the presence of a binary surfactant mixture: CTAB (cetyl trimethyl ammonium bromide) and PVP (poly-vinylpyrrolidone) with their various concentrations. Characterizations of the samples have been carried out by using UV-Vis spectroscopy, XRD and FESEM.UV-Vis spectra showed that the gold particles have grown with a various geometrical forms, such as spherical and others. XRD results informed that the presence of two peaks at 2θ: 38.195oand 44.393oindicated the gold nanoplates, with their crystal orientation of (111) and (200). FESEM images showed the edge-length size of nanoplates was dominated in the range of 11nm to 50 nm, with various morphologies of nanoplates, such as hexagonal,truncated hexagonal, triangular, square and spherical shapes.

Composite lead sulphide/phthalocyanine thin films were produced for the first time by exposure of thin spun films of a lipophilic lead phthalocyanine derivative to H/sub 2/S gas. The formation of lead sulphide was confirmed by Raman and X-ray photoelectron spectroscopy measurements. UV-visible absorption and photoluminescence spectral measurements as well as a film morphology study using atomic force microscopy indicate the formation of lead sulphide clusters. From the blue spectral shift of the fundamental adsorption band, the size of the PbS clusters was estimated to be 2.24 nm.

CdS nanoparticles were formed within LB films of either Cd salts of stearic acid (SA) or calix[8]arene (CA) by exposing the samples to H2S gas. A series of DC and AC electrical measurements were performed for both planar and sandwich structures over a wide range of frequencies. Exponential behaviour of the DC I-V characteristics of the sandwich structures is typical for electron tunnelling through multilayered LB films. The conductivity value decreases after formation of CdS nanoparticles in the film, which is believed to be caused by the reduced layer-by-layer film order. AC measurements show a traditional insulating behaviour for all kind of films studied. Formation of CdS clusters in the LB films resulted in the decrease in both the capacitance and AC conductivity, which can be interpreted by the drop in the polarisability in disordered LB films. (C) 2002 Elsevier Science B.V. All rights reserved.

Binderless activated carbon monolith (ACM) was prepared from pre-carbonized rubber wood sawdust (RWSD). The effect of the carbonization temperature (400, 500, 600, 700, 800 dan 900 °C) on porosity characteristic of the ACM have been studied. The optimum carbonization temperature for obtaining ACM with high surface area of 600 °C with CO2 activation at 800 °C for one hour. At this condition, the surface area as high as 733 m2 g−1 could be successfully obtained. By improved the activation temperature at 900 °C for 2.5 h, it was found that the surface area of 860 m2 g−1. For this condition, the ACM exhibit the specific capacitance of 90 F g−1. In addition the termogravimertic (TG)-differential termografimertic (DTG) and field emission scanning electron microscope (FESEM) measurement were also performed on the ACMs and the result has been studied. Finally, it was conclude that the high surface area of ACM from RWSD could be produced by proper selections of carbonization and activation condition.

Silver nanosheets, with average size tunable from 30 to 100 nm, have been synthesized onto solid substrates by using seed-mediated growth method. The growth of silver nanosheets have been carried out at temperature of 30°C in the presence of a binary surfactant mixture: cetyl trimethyl ammonium bromide (CTAB) and poly-vinyl pyrrolidone (PVP) with their various concentrations. The effect of concentration of the surfactants on the grown silver nanosheets were evaluated. Characterizations of the samples have been performed by using UV-Vis spectroscopy, X-ray diffraction (XRD) and field-emission scanning electron microscope (FESEM). UV-Vis spectra showed that the silver nanoparticles have grown with a various geometrical forms. XRD results confirmed that the presence of two peaks at 2θ: 38.119° and 44.305° indicated the silver nanosheets, with their crystal orientation of (111) and (200). FESEM images of the best samples showed the edge-length size of silver nanosheets was dominated in the range of 30-100 nm, with various morphologies of nanosheets, such as triangular, hexagonal and spherical shapes.

In this paper, a composite electrode was prepared from a mixture of activated carbon derived from precarbonization of cassava peel (CP) and carbon nanotubes (CNTs). The activated carbon was produced by pyrolysis process using ZnCl2 as an activation agent. A N2 adsorption-desorption analysis for the sample indicated that the BET surface area of the activated carbon was 1336 m2 g−1. Difference percentage of CNTs of 0, 5, 10, 15 and 20% with 5% of PVDF binder were added into CP based activated carbon in order to fabricate the composite electrodes. The morphology and structure of the composite electrodes were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The SEM image observed that the distribution of CNTs was homogeneous between carbon particles and the XRD pattern shown the amorphous structure of the sample. The electrodes were fabricated for supercapacitor cells with 316L stainless steel as current collector and 1 M sulfuric acid as electrolyte. An electrochemic...

In this study, an optimation growth of platinum (PtNs) and palladium (PdNs) nanoparticles has successfully grown on stainless steel 316L and activated carbon pellet as substrates. PtNs and PdNs were grown on the substrates by wet chemical method. The effect of concentration of ascorbic acid and multi-growth step had shown the significantly in density and particle size distribution on the both substrates. The morphology and the structure of PtNs and PdNs were characterized by a field-emission scanning electron microscope (FESEM), X-ray diffraction (XRD), respectively. Homogenous particles size and high density of PtNs and PdNs on the substrates were also successfully grown with current method.

Composite phthalocyanine thin films were produced for the first time by exposure of thin films of an organic solvent soluble lead phthalocyanine derivative to H/sub 2/S gas. UV-visible absorption and photoluminescence spectral measurements indicate the probable formation of lead sulfide clusters, while the film structure and morphology were studied with atomic force microscopy.

A network of gold nanostructures exhibiting one-dimensional gold nanostructure properties may become a prospective novel structure for optical, electrical and catalytic applications benefited by its unusual characteristics resulting from the collective properties of individual nanostructures in the network. In this paper, we demonstrate a facile method for the formation of high-density gold nanonetwork film on the substrate surface composed of quasi-1D nanoparticles (typically fusiform) with length ca. 10 nm - via reduction of gold ions in the presence of nanoseeds attached surface, binary surfactants of cetyltrimethylammonium bromide and hexamethyleneteramine and Ag+ ions. The length of the nanonetworks can be up to ca. 100 nm, which corresponds to the aspect ratio of ca. 10. The quasi-1D gold nanostructures as well as the nanonetworks were found to be sensitive to the binary surfactants system and the Ag+ ions as they can only be formed if all the chemicals are available in the reaction. The nanonetworks exhibit unique 1D optical properties with the presence of transverse and longitudinal surface plasmon resonance absorption. Owing to their peculiar structures that are composed of small quasi-1D nanoparticles, the nanonetworks may produce unusual optical and catalytic properties, which are potentially used in surface-enhanced Raman scattering, catalysis and optical and non-linear optical applications.