Volume Of Precursor Solution Research Articles

Synthesis of highly stable Li4SiO4-based CO2 sorbents using polysilicon by-product SiCl4 as raw material

With the rapid development of the photovoltaic industry, the demand for polysilicon has been continuously increasing. In the production of polysilicon, a large amount of SiCl4 will inevitably be produced as a by-product. Proper treatment of this SiCl4 is crucial for reducing environmental pollution and controlling the production costs of polysilicon. In this study, a by-product of polysilicon production SiCl4 was utilized as a silicon source to synthesize the high-temperature CO2 sorbent Li4SiO4. The effects of SiCl4 content in the precursor solution and CO2 volume concentration on the adsorption performance of the sorbents were thoroughly investigated. The results showed that Li4SiO4-x (x = 0.5, 1.5, and 2.5) exhibited excellent adsorption performance and cyclic stability under 100 vol% CO2 atmosphere, with adsorption capacities of 26.29, 29.66, and 34.04 wt% after 15 cycles, respectively. Additionally, the study found that as the CO2 concentration decreased from 100 vol% to 50 vol% and 15 vol%, the adsorption equilibrium temperature showed a slight shift to the left, and the adsorption capacity also decreased to varying degrees, but the material maintained good cycle stability throughout the process. In summary, the synthesis of Li4SiO4 from SiCl4 has broad application prospects.

Single Crystal Perovskite MAPbBr3 Prepared by Using Anti-solvent Vapor-assisted Crystallization Method

Perovskite methylammonium lead tri-bromide (MAPbBr3) material has gained a lot of attention in the past few years due to its impressive optoelectronic properties, which is suitable for high efficiency and sensitivity X-ray photodetector. Compared to polycrystalline crystal structure, MAPbBr3 single crystal is more ideal for X-ray photodetector because lack of grain boundary therefore produce more sensitive photodetector. However, a cubic structure and large crystal dimension is highly required to adjust into the flat-panel detector configuration. In this research, MAPbBr3 perovskite crystals were synthesized by using Anti-solvent Vapor-assisted Crystallization (AVC) at room temperature using dimethylformamide (DMF) as solvent and Dichloromethane (DCM) as antisolvent. The precursors for the MAPbBr3 solution were prepared by varying the molar ratio of MABr:PbBr2 as precursor solution. The crystal growth rate was controlled by varying the volume ratio of DCM and MAPbBr3 precursor solution. The obtained largest crystal size of 10 mm × 10 mm was prepared with a volume ratio of DCM and precursor is 3 and a volume of precursor solution is 6 ml. The XRD of large cubic MAPbBr3 crystal showed a peak of (100) plane, which indicates a single crystal oriented in a-axis direction. The Raman spectra peaks of perovskite MAPbBr3 crystals showed organic (MA+) and inorganic (PbBr2 −) bonds in a cubic phase of single crystal MAPbBr3. All samples that were prepared with different ratios of DCM and precursor solution have the same Raman spectra, which confirm that all MAPbBr3 crystals have cubic crystal structure.

Synthesis and study of the effects of precursor solution volume, substrate type, and pulsed deposition on the physical properties of titanium dioxide thin films for using as a photoanode

Synthesis and study of the effects of precursor solution volume, substrate type, and pulsed deposition on the physical properties of titanium dioxide thin films for using as a photoanode

Studies on nanocomposites nanoplates and pervoskite nanorod thin films

Nano crystalline nickel oxide thin films of different film thickness were deposited onto glass substrate at 350 oC by varying volume of precursor solution using spray pyrolysis technique. This structural, morphological and microstructure properties were investigated using XRD, FE-SEM and TEM. The element composition was studied using EDAX. It is found that increase in the volume of sprayed solution leads to the increment in film thickness and amelioration of crystallinity of the film. The results are discussed and interpreted.

Engineering of physical properties of spray-deposited nanocrystalline Sb2O3 thin films by phase transformation

Nanostructured Sb2O3 thin films have been deposited onto glass substrates by using the chemical spray pyrolysis technique, and the effect of precursor solution volume on the physical properties was investigated for the first time. The prepared films were characterized in detail by using x-ray diffraction, field-emission scanning electron microscopy with energy dispersive x-ray analysis (FESEM-EDAX), UV-vis absorption and transmission spectroscopy, Raman spectroscopy analysis and electrical resistivity measurement. X-ray diffraction analysis shows that the senarmontite cubic phase is completely transferred to the valentinite orthorhombic phase as the precursor solution volume is increased. This phase transformation as a function of precursor volume is discussed in detail. The FESEM-EDAX analysis reconfirms the phase change showing well-defined nano-dimensional cubic hexagonal and orthorhombic octahedral morphologies with excellent stoichiometry. The optical property studies show that the bandgap energy of Sb2O3 varies from 3.43–3.98 eV as a function of precursor quantity. The as-grown Sb2O3 thin films are semiconducting in nature. The measured values of electrical resistivity and activation energy are found to be dependent on the spray solution volume. The electrical resistivity of deposited Sb2O3 thin films shows variation from 26.15 × 102–34.27 × 102 Ω cm and the activation energy of the films is in the order of 0.763–0.773 eV.

Influence of controlled Pd nanoparticles decorated TiO2 nanowire arrays for efficient photoelectrochemical water splitting

This work depicts the synthesis of controllable Pd nanoparticles decorated TiO2 nanowire arrays by electrospray technique. By varying the substrate temperature and volume of precursor solution, Pd/TiO2 hybrid structure with different sizes and deposition yield was precisely controlled. The highest photocurrent density of the Pd/TiO2 photoanode was 1.4 mA cm−2 at 1.23 V vs. RHE, which was approximately 5 times higher than the pristine TiO2. The onset potential with a significant cathodic shift of 80 mV compared to the pristine TiO2 was also observed. To the best of our knowledge, the obtained photocurrent showed the optimal photocurrent density and high stability compared with previous reports. It is also found that the photoelectrochemical performance is closely related to the size and deposition quantity of Pd nanoparticles. According to the results, the enhanced PEC performance can be attributed to the Schottky junction, charge transfer and the enhancement about the separation efficiency of the photogenerated electrons and holes betweenTiO2 and Pd NPs. This result demonstrated that this method may design a new and green strategy for synthesizing the well-defined morphologies, compositions, and sizes of the hybrid nanomaterial for photocatalytic hydrogen generation, photocatalytic CO2 reduction and photosynthesis of organic molecules.

Precursor solution volume-dependent ligand-assisted synthesis of CH3NH3PbBr3 perovskite nanocrystals

Ligand-assisted reprecipitation (LARP) technique is a powerful approach for the synthesis of organometal halide perovskite nanocrystals (PNCs). The morphology and surface property of the formed PNCs which determine their optical properties are ultrasensitive to the synthetic parameters. To guarantee the batch-to-batch reproducibility of PNCs with excellent optical properties, it is of central importance to better understand the factors influencing the formation of PNCs during LARP process. Herein the dual-factor of the amount of perovskite precursor and the polarity of mixture solvent was modified by varying precursor solution volume (PSV) in the LARP system. The concentration, size, surface state and optical properties of the synthesized CH3NH3PbBr3 PNCs as a function of PSV were systematically investigated aiming to understand the influence of the dual-factor on the nucleation and growth of PNCs. Experimental results revealed that few crystal nuclei was generated due to lower amount of precursor at lower PSV, which was favorable for the growth of large perovskite crystals. At the higher PSV, the inhibition of crystal growth with increased amount of precursor was compensated by increasing the polarity of mixture solvent, which led to the dissolution of surface ligands and eventually growth of large perovskite crystals. The obtained results on PSV-dependent synthesis of PNCs will be used as a guide to optimize the synthetic parameters in the LARP process.

Volume of precursor solution effect on the properties of SnO2 thin films prepared by nebulized spray pyrolysis technique

Undoped SnO2 thin films have been deposited on amorphous glass substrates with different precursor solution volume (10, 15, 20 and 25 ml) using simple and cost-effective nebulized spray pyrolysis technique. The influence of precursor solution on structural, optical, photoluminescence and electrical properties had been studied. The X-ray diffraction spectra prove the polycrystalline nature of SnO2 with tetragonal structure. All the films show a preferred growth orientation along (110) diffraction plane. The average transmittance of SnO2 thin films varied between 82 and 75% in the visible as well as IR region. The band gap energy decreases from 3.74 to 3.64 eV corresponding to direct transitions with the precursor solution volume had increased from 10 to 20 ml and then increased as 3.72 eV for 25 ml. SEM pictures demonstrated polyhedrons like grains. EDX confirmed the existence of Sn and O elements in all the prepared SnO2 thin films. Photoluminescence spectra at room temperature revealed that the four emission bands in all the samples such as sharp dominant peak at 361 nm with shoulder peak at 377 nm (UV region), a broad and low intensity peak at 492 nm (blue region) and 519 nm (green region). The electrical parameters were examined by Hall effect measurements, which demonstrated that the film prepared at 20 ml precursor solution volume possess minimum resistivity 2.76 × 10−3 Ω-cm with activation energy 0.10 eV and maximum figure of merit 1.54 × 10−2 (Ω/sq)−1.

Solution volume effect on structural, optical and photovoltaic properties of nebulizer spray deposited SnS thin films

SnS thin films deposited using nebulizer spray pyrolysis method by changing the precursor solution volume is reported in this work. The prepared films were characterized by X-ray diffraction, scanning electron microscopy, Raman spectrum, atomic force microscopy, EDAX, UV–Vis spectroscopy and PL spectrofluorometer analysis. Electrical studies done using Hall Effect measurement for the film is also reported. Structural and surface morphological analyses showed high crystalline single phase of SnS thin films with relatively low surface roughness. Optical studies done on the films revealed a decrease in band gap from 1.82 to 1.73 eV for the increase of solution volume from 5 to 15 ml. The CdS film prepared by this method showed a maximum of 75% transmittance and band gap of 2.51 eV. Prepared SnS thin film showed p-type conductivity with resistivity 2.01 × 101 Ω cm and carrier concentration 4.71 × 1017/cm3. A FTO/n-CdS/p-SnS heterostructure was also fabricated using the grown film and studied its photoconductivity.

Investigation on V2O5 Thin Films Prepared by Spray Pyrolysis Technique

The spray pyrolysis technique was employed to deposit V2O5 thin films on a glass substrate. By varying the precursor solution volume from 10[Formula: see text]mL to 50[Formula: see text]mL in steps of 10[Formula: see text]mL, films of various thicknesses were prepared. Orthorhombic polycrystalline V2O5 films were inferred from the XRD pattern irrespective of precursor solution volume. The micro-Raman studies suggested that annealed V2O5 thin film has good crystallinity. The effect of precursor solution volume on morphological and optical properties were analysed and reported.

In situ X-ray absorption fine structure analysis of redox reactions of nickel species with variable particle sizes supported on silica

The chemical states of Ni species were systematically investigated using an in situ XAFS technique for a series of SiO2-supported Ni catalysts with different Ni particle sizes. The Ni particles were refined by varying the Ni loading in the range between 0.10 and 5wt% and by adding citric acid into the precursor solution. An in situ observation cell for fluorescence-yield XAFS measurements was developed for the dilute Ni catalysts. The chemical state of the supported Ni species converted between Ni(0) and NiO, and no other stable species were formed during the temperature-programmed oxidation and reduction processes. Refinement of the Ni particles resulted in decreasing the oxidation temperature and increasing the reduction temperature. These shifts were explained by the affinity of NiO to SiO2, and more effective stabilization was thus anticipated for flattened small NiO particles with an increased contact area. In addition, the inhomogeneous distribution of small Ni particles observed for dilute catalysts was explained in terms of the precursor solution volume when nuclei of the precursor compound precipitated on SiO2 during the drying process.

Influence of precursor solution volume on the properties of tin disulphide (SnS2) thin films prepared by nebulized spray pyrolysis technique

Tin disulphide (SnS2) thin films have been deposited with various precursor solution volumes (5–25ml) by nebulized spray pyrolysis technique onto glass substrates. The X-ray diffraction studies revealed that the as-deposited SnS2 thin films were polycrystalline in nature and having a hexagonal structure with a single preferential orientation along (001) plane. SEM analysis revealed that all the thin films had platelet-like grains. The EDAX analysis confirmed the presence of tin and sulphur. Multiple interference effect was predominant in all these thin films in the wavelength region of 500–1100nm. Direct band gap values were found to decrease up to 2.67eV with the increase in precursor solution volumes from 5 to 20ml and increased further. All the SnS2 thin films were found to be n-type semiconductors. The better conductivity and mobility noticed at the precursor solution volume of 20ml are explained by carrier concentration and crystallites. The Activation energy of these films was determined by plotting a graph between log (resistivity) versus reciprocal temperature using a four-probe method.

Investigations on the structural, electrical and optical properties of thin films of CdO(111)

Thin films of cadmium oxide (CdO) were prepared by simple nebulized pyrolysis technique by spraying on the amorphous glass substrates at five different volumes (5, 10, 15, 20 and 25 ml) of precursor cadmium acetate dihydrate solution. X-ray diffraction analysis reveals that the prepared films were oriented along with prominent (111) plane having cubic structure in CdO matrix. The surface morphology of these thin films showed sphere like structure was observed from scanning electron microscopic study. Transparency of these samples had decreased from 95 to 80% at longer wavelengths (900–1100 nm) with an increase in precursor solution volume. The energy band gap increases from 2.30 to 2.49 eV belonging to direct transition as the precursor solution volume had increased up to 20 ml and decreased for 25 ml. The presence of the absorption peak around 650 cm−1 corresponding to CdO bond was confirmed by FTIR spectrum. The emission spectrum of CdO thin films were investigated by fluorescence spectrum recorded at room temperature. Hall Effect measurement was carried out to investigate the electrical properties of the as deposited CdO thin films. The resistivity decreased from 36 × 10−2 to 7.54 × 10−3 Ω-cm and the activation energy (Ea) had decreased from 0.20 to 0.096 eV. The hot probe characterization proved, all these thin films were n-type semiconductor.

Structural, surface and mechanical characterization of spray-deposited molybdenum disulfide thin films

Molybdenum disulfide (MoS2) was deposited with the precursor salt of ammonium molybdate tetrahydrate and thiourea on glass substrate at various precursor solution volume (10–50mL) using the spray pyrolysis technique. The X-ray diffraction pattern indicates the polycrystalline nature of the film with a hexagonal structure and the occurrence of peak shift due to stacking fault. The field-emission scanning electron micrograph shows the increment in grain growth with increase in the precursor solution volume, leading to the conversion of grains to nanoflakes. Energy dispersive spectrum confirms the presence of molybdenum and sulfur. Vickers microhardness shows increament in microhardness with decrease in the precursor solution volume. The mechanical properties related to microhardness were analyzed. Raman analysis confirms the hexagonal structure of MoS2 with the presence of vibrational modes.

Solvent volume driven ZnO nanopetals thin films: Spray pyrolysis

Nanostructured ZnO thin films were spray pyrolysis deposited on glass substrates using the zinc acetate dihydrate as precursor at the substrate temperature of 523K. The effect of precursor solution volume on the structural, morphological, electrical, optical and gas sensing properties of ZnO thin film was investigated. The growth of nanopetals morphology was observed for the film deposited using 30ml. Enhanced electrical conductivity was observed for the film with nanopetals morphology but the optical transmittance was found to be decreased up to 25% than that of other films. The influence of tensile and compressive stress in the prepared samples was investigated. Further the room temperature acetaldehyde sensing behaviour of the ZnO film deposited using 45ml precursor volume is reported.

Influence of precursor solution volume on the properties of spray deposited α-MoO3 thin films

α-MoO3 thin films were deposited onto a glass substrate with 0.01M ammonium heptamolybdate tetrahydrate as a precursor salt and deionized water as solvent using spray pyrolysis technique. The influence of precursor solution volume on the structural, morphological, optical and electrical properties were analysed and reported.

Cobalt doping, etching, and attachment of gold nanoparticles and quantum dots on ZnO nanorods

AbstractZnO is an important material for optoelectronic applications such as solar cells and sensors due to its wide band gap and functional properties. Optimizing the growth mechanisms of ZnO nanorods as grown in a low temperature, wet chemical method will allow for an enhancement of material, optical, and electronic properties in a low cost production method. Our group fabricated nanorods on indium tin oxide (ITO) and glass substrates. The alignment and optical properties of the ZnO nanorods depend greatly on the initial seed layer of (doped) ZnO as well as the growth parameters. In this study we investigated the changes in the optical absorption properties of ZnO nanorods doped with cobalt. Cobalt doping was achieved by adding a percentage of cobalt chloride to the total volume of chemical bath precursor solution of Zinc nitrate and hexamethylentramine. Optical and energy dispersive X‐ray measurements reveal that the optical absorption of ZnO nanorods extends from 385 nm to 700 nm when doped with cobalt from 0.1 at.% to 9.7 at.%. In addition, we investigated the selective etching of ZnO with 3 molar concentrations of potassium chloride solution. Etching under 3 molar solution concentration produced ZnO nanotube structures that can be used for enhancing optical and chemical sensitivity. We also present absorption profiles of ZnO nanorods decorated with metallic nano particles of gold as well as CdSe quantum dots (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Sintering and Dielectric Properties of BaTiO<sub>3</sub> Nano-Particle Prepared by Aerosol Plasma Pyrolysis Process

BaTiO3 nano-sized powders were successfully prepared by spray pyrolysis using multiphase plasma under the air atmosphere. The particles characteristics of BaTiO3 nano-sized powders were studied by SEM and XRD. The effect of volume of arc plasma and precursor solution on the formation of BaTiO3 nano-sized powders was investigated. The use of Ba-Ti complex precursor solution derived from lactic acid led to formation of tetragonal BaTiO3 nano-sized powders with 140 nm size. As for BaTiO3 ceramics, the effect of sintering temperature on relative density and the temperature dependence of dielectric properties were investigated.