Shape Of Nanoplates Research Articles

Influence of different molar concentration on the structural, optical, electrical and photo diode properties of MoO3 thin films

This article discusses an eco-friendly method for creating metal-insulator-semiconductor (MIS) diodes. MoO3 thin films are prepared at different mole concentrations (0.01, 0.03, 0.05 and 0.07 M) using a Jet Nebulizer Spray Pyrolysis (JNSP) methodology. An orthorhombic phase, which is of special interest because of its potential in electronic applications, was discovered by structural investigation using X-ray diffraction (XRD) in the 0.05 M MoO3 film. Field emission scanning electron microscopy (FE-SEM) pictures of the 0.05 M MoO3 film show a distinct nanoplate shape, indicating positive characteristics for photovoltaic applications. UV–Vis spectroscopy revealed an energy bandgap of 3.21 eV for this concentration. This corresponds to the requisite electronic parameters for a high-performance MIS diode. Then the DC electrical conductivity of the films showed a monotonic rise with the concentration of MoO3, peaking at 0.05 M, suggesting improved carrier transport characteristics. The I–V characteristics of the Cu/MoO3/p-Si diodes revealed that current flows mostly across interfaces and is controlled by carrier concentration. The 0.05 M MoO3 substance exhibited a considerable increase in photocurrent. This work explains the optimized MoO3 concentration and the morphology using the JNSP approach can result in the production of highly efficient MIS diodes suited for a wide range of optoelectronic applications.

Radially polarized light in single particle optical extinction microscopy identifies silver nanoplates

Quantifying the optical extinction cross section of a single plasmonic nanoparticle (NP) has recently emerged as a powerful method to characterize the NP morphometry, i.e., size and shape, with a precision comparable to electron microscopy while using a simple optical microscope. Here, we enhance the capabilities of extinction microscopy by introducing a high numerical aperture annular illumination coupled with a radial polarizer to generate a strong axial polarization component. This enables us to probe the NP response to axial polarized light, and, in turn, to distinguish flat-lying nanoplates from other geometries. Polarization-resolved optical extinction cross sections were acquired on 219 individual colloidal silver NPs of a nominally triangular nanoplate shape but, in practice, exhibiting heterogeneous morphometries, including decahedrons and non-plate spheroids. An unsupervised machine learning cluster analysis algorithm was developed, which allowed us to separate NPs into different groups, owing to the measured differences in cross sections. Comparison of the measurements with a computational model of the absorption and scattering cross section accounting for nanoplates of varying geometries beyond simple triangles provided insight into the NP shape of each group. The results provide a significant improvement of polarization-resolved optical extinction microscopy to reconstruct NP shapes, further boosting the utility of the method as an alternative to electron microscopy analysis.

Magnetic suppression for a possible Fe-poor organic–inorganic hybrid superconductor Fe14Se16(tepa)0.8 (tepa = tetraethylenepentamine) with a superconducting transition at ∼42 K

Composition/structure-dependent superconductivity for FeSe-based superconductors attracted great attention not only due to their high superconducting transition temperatures (TC), but also for understanding the origin of iron-based superconductivity. Here, we report a new Fe-poor organic-inorganic hybrid material Fe14Se16(tepa)0.8 with a paramagnetic-diamagnetic transition at ∼42 K grown by a high-temperature organic-solution-phase method with soluble iron/selenium sources in a tepa solution, alternative to previous intercalation strategies. The Fe14Se16(tepa)0.8 phase is in a tetragonal layered hybrid structure with a nanoplate shape. Composition analyses reveal a Fe-poor characteristic of the hybrid in contrast to previous FeSe-intercalated superconductor, and selected area electron diffraction pattern is featured by Fe3Se4 superstructures with a √2 × √2 of Fe vacancy order. Ab initio density functional calculations show that minus Fe3Se4 ions are stable in the hybrid and ∼0.25e−/Fe0.75Se is obviously larger than the reported values of approximately 0.2e−/FeSe in other FeSe-intercalated superconductors. Typical hysteresis loops and temperature dependence of dc/ac susceptibilities of the Fe14Se16(tepa)0.8 measured below ∼42 K suggest a presence of the Meissner effect in this material. Effects of synthesis conditions on structures and magnetic properties of the hybrids show a magnetic evolution from a long-range ferrimagnetic (FIM) order of Fe14Se16(tepa) to a coexistence of FIM and superconducting (SC) orders of Fe14Se16(tepa)0.9 and an SC order of Fe14Se16(tepa)0.8. X-ray absorption spectrum (XAS) confirms the presence of ferric/ferrous irons. Mössbauer studies reveal that the high-TC superconductivity originates from a suppression of the FIM order through tuning the spin states of irons from high-spin Fe3+ (S = 5/2) and Fe2+ (S = 2) in the Fe14Se16(tepa) to low-spin Fe3+ (S = 1/2) and Fe2+ (S = 0) in the Fe14Se16(tepa)0.8. Although no zero resistance is detected even at a temperature of 2 K, the resistivity at 2 K decreases by more than 1600 times compared to that in a normal state calculated by a variable range hopping (VRH) model, suggesting that the high-TC superconductivity of Fe14Se16(tepa)0.8 is possible.

Charge ordering at a dielectric gate in itinerant metallic states with low-field memristor properties in VO2 thin films

Vanadium dioxide (VO2) − a non-stoichiometric oxide semiconductor (SC) offers exotic properties at a self-confined structure of correlated 3d1-electrons (spins) useful for non-volatile memory devices, smart switches, and human brain-inspired neuromorphic devices. Poor chemical stability and fragile nature limit its technologies of thin films. In view of resolving some of these issues, we developed polymer stabilized VO2 films (thickness t ≤ 100 nm), using VO2 nanocolloids in poly(vinylpyrrolidone) (PVP) (as a VO2 dispersoid, a molecular template, and a film former) in water, at a (100) Si(p++) substrate. Using a nano SiO2/TiO2 gate (t ≤ 10 nm), VO2 is grown (011) preferentially in a confined shape of nanoplates (nanocrystals) along the films, mostly of 15 to 40 nm widths at 20–30 nm crystallite size. The results are described with X-ray diffraction, surface topologies, lattice images, and X-ray photoelectron spectroscopy (XPS) of films in the variable charges 2V4+ → V3+ + V5+ order at the itinerant metallic states. A significant V5+-3d0, ≤ 33 at%, is shown in the XPS bands, which induces metallic states at conducting ‘V4+ → V5+ + e−’ channels. So, a charge-regulated SC → metal transition incurs via an induced M1 → R-VO2 metallic state near room temperature. A memristor VO2@TiO2/Si so made renders a wide current-voltage (I-V) loop at room temperature, with a leakage current that is well controlled at a high-k TiO2 gate. It exhibits a reversible switching at a duly small threshold field, Vt ≤ 0.2 V. This is the smallest Vt tuned so far beneficial for the low field, ≤ 1.0 V, devices. The charge models corroborate the effect of field-induced charge order at the interfaces of ‘conducting through channels’, regulating a reversible I-V hysteresis in an on-off cycle.

Effect of ammonium chloride on the morphology of hexagonal boron nitride prepared by magnesium thermal reduction

AbstractHexagonal boron nitride (h‐BN) crystals with cylindrical and nanoplate shape were prepared by the magnesium thermal reduction method. A simple and novel strategy successfully controlled the preferred growth direction of h‐BN crystal by adding a small amount of ammonium chloride to the reaction system, realized the transformation of the h‐BN crystal growth mode from cylindrical to nanoplate, and the thickness of h‐BN crystal nanoplates rapidly decreased from 2 μm to 40 nm. XRD results showed that the ammonium chloride content also significantly promoted the crystallinity of the synthesized h‐BN nanoplates, and the G.I. index decreased from 2.4 to 1.9. Raman and TEM results showed that the crystallinity of synthesized h‐BN was close to the properties of the single crystal.

Synthesis and H2S Gas Sensing Characteritics of Nanostructured V2O5

In this study, V2O5 nanomaterials were successfully synthesized by a facile hydrothermal method and tested for application in preparing toxic H2S gas sensor. SEM image shows that the material has the shape of nanoplates with different sizes ranging from 100 to 500 nm. The XRD pattern shows that the material has a single phase of Orthorhombic crystal of V2O5. The results of the gas sensitivity survey show that the material good respond to H2S at low concentrations (2.5-20 ppm) with relatively fast response and recovery time. This study demonstrates the potential of application of V2O5 material in H2S gas sensors.

Polyester fabric modification through fabrication of nano-copper compounds

This research introduces a new method of polyester fabric surface modification in order to achieve distinctive features. The copper sulfate, sodium hydroxide and cetyl trimethylammonium bromide (CTAB) were used to synthesize copper nanoparticles, and loaded on the polyester fabric surface. The optimal sample was considered by SEM-EDX, FT-IR and XRD devices. SEM images showed copper nanoparticles in shape of nano-plates with 150 to 600 nm in length and thickness of about 30 nm. The best results obtained on the modified fabric processed at boil for 120 min. According to the results of experiments CuO and Cu0 were synthesized on the fabric.

Hollow carbon architectures with mesoporous shells via self-sacrificial templating strategy using metal-organic frameworks

A self-template method is reported to prepare hollow-structured and ordered mesoporous carbon (HOMC) nanoplates by depositing resol-F127 monomicelles onto the surface of metal-organic-framework nanosheets, followed by hydrothermal reaction and carbonization. From adding FeCl 3 during the hydrothermal reaction, Fe-doped HOMC can be obtained after carbonization, which exhibits higher electrocatalytic activity and efficiency than the commercial Pt/C during the oxygen reduction reaction • Hollow-structured OMC (HOMC) nanosheets are prepared by a self-template strategy. • Fe-doped HOMC is obtained as a result from adding FeCl 3 during assembly process. • The Fe-doped HOMC exhibits outstanding electrocatalytic ORR performance. The rational design and fabrication of ordered mesoporous materials with highly exposed surface area are of great significance to address the fundamental challenges in electrochemistry-related applications by providing more active sites and fast ion/gas diffusion channel. In this work, a self-template method is reported to prepare hollow-structured mesoporous carbon (HOMC) nanoplates by depositing resol-F127 micelles onto the surface of metal–organic-framework (MOF) nanoplates, followed by hydrothermal reaction and carbonization. The parameters influencing the morphology and microstructure of the HOMC materials, i.e. , the MOF-to-resol-F127 ratio and the concentration of resol-F127 micelles, are systematically investigated. Fe-doped HOMC (Fe/HOMC) is obtained after carbonization, as a result from adding FeCl 3 during the hydrothermal reaction. Benefiting from morphological aspects, such as the nanoplate shape, the hollow structure, and mesoporous walls, the Fe/HOMC exhibits higher electrocatalytic activity and efficiency than the commercial Pt/C during oxygen reduction reaction (ORR). In addition, when compared to traditional Pt/C benchmark, the Fe/HOMC shows a superior durability and tolerance to methanol poisoning while operating for ORR. The assembled Zn-air battery possesses high power densities with excellent cycling stability. The strategy proposed here can provide a new avenue for the design of ordered mesoporous materials with hollow structure for a wide variety of applications.

Photo sensitizing and electrochemical performance analysis of mixed natural dye and nanostructured ZnO based DSSC

The paper highlights the enactment of the natural dyes, like purple cabbage, spinach, turmeric and their mixture as a photo-sensitizer, with nanostructured zinc oxide (ZnO) as a photo-anode, based dye-sensitized solar cell (DSSC). The field emission scanning electron microscopic image of ZnO, prepared by chemical bath deposition process, proclaims two different types of morphology, nano-wire and nano-plate shape. The photo sensitizing properties of the natural dyes and their mixed part are explored through FTIR spectra and UV-vis light absorbance characteristics. The FTIR spectra explore the presence of different anchoring chemical groups which confirm the strong anchoring bond with ZnO and enhancement of electron mobility. The diffused reflectance spectra (DRS) of dye-loaded ZnO films incisive the absorption of dye on the mesoporous ZnO surface. The relative energy band positions of individual and mixed dye, yield stable execution of the cell that has been performed through the cyclic voltammeter. The driving force energy requirement for effortless transport of electron from the mixed dye to the conduction band of ZnO is revealed lowers (0.34 eV) as compared to individual dyes. Electrochemical impedance spectroscopy (EIS) analysis has been executed to find the charge transfer resistance, total bulk resistance, recombination loss through Nyquist plots and Bode plots. These characteristics pretense as the mixed dye has an eminent rate of electron transportation and lower recombination loss with longer electron lifetime. The photon to electrical power conversion efficiencies of purple cabbage, spinach, turmeric and their mix dyes are explored as 0.1015%, 0.1312%, 0.3045%, and 0.602%, respectively under same simulated light condition. The mixed dye reveals the stable performance of the cell with the highest conversion efficiency due to the absorption of an extensive range of the solar spectrum and well-suited electrochemical responses.

An analytical study of vibration in functionally graded piezoelectric nanoplates: nonlocal strain gradient theory

In this paper, we analytically study vibration of functionally graded piezoelectric (FGP) nanoplates based on the nonlocal strain gradient theory. The top and bottom surfaces of the nanoplate are made of PZT-5H and PZT-4, respectively. We employ Hamilton’s principle and derive the governing differential equations. Then, we use Navier’s solution to obtain the natural frequencies of the FGP nanoplate. In the first step, we compare our results with the obtained results for the piezoelectric nanoplates in the previous studies. In the second step, we neglect the piezoelectric effect and compare our results with those obtained for the functionally graded (FG) nanoplates. Finally, the effects of the FG power index, the nonlocal parameter, the aspect ratio, and the side-tothickness ratio, and the nanoplate shape on natural frequencies are investigated.

Incorporating nanoplate-like hydroxyapatite into polylactide for biomimetic nanocomposites via direct melt intercalation

Natural apatite in human bones is nanoplate shaped. However, nanocomposites with nanoplate-like hydroxyapatite (np-HAp) have been poorly exploited. Herein, polylactide (PLA) nanocomposites reinforced with biomimetic np-HAp were fabricated by exfoliating laminated hydroxyapatite via direct melt intercalation method which was realized using scalable extrusion and injection molding processes. The physicochemical properties of the resulting np-HAp/PLA nanocomposites were characterized with X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and mechanical testing. In addition, the biocompatibility and in vitro bioactivity were systematically investigated. The influence of np-HAp content on mechanical properties, thermal stability, hydrophilicity, and particularly biocompatibility and in vitro bioactivity were evaluated. It is found that the np-HAp/PLA nanocomposites not only show improved mechanical properties and thermal stability, but also exhibit improved cell spreading and proliferation. More importantly, the np-HAp/PLA nanocomposites exhibit excellent in vitro bioactivity due to the biomimetic nanoplate shape that has large surface area and abundant exposed active sites than other HAp shapes. It has been demonstrated that such unique nanocomposites show promising as a new biomaterial for load-bearing orthopedic implants.

Preparation and Antibacterial Activity Studies of TiO2 Nanostructured Materials

Different morphologies of nanostructured TiO2 materials can be tailor-made as a function of growth time varied from 1 to 7 h with a step of 2 h. TiO2 nanostructures were prepared on titanium foil by a facile water-assisted chemical vapor deposition method at 850°C. Scanning electron microscopy examination of the samples reveled that, under the treatment time of 7 h, the morphology of nanostructures transformed from cubic nanostructure-like to agglomerated nanorod-like and nanoplate shape. The X-ray diffraction through synthesized TiO2 nanostructures exhibited the crystalline structure of rutile TiO2 formed during the synthesis process. X-ray diffraction analysis showed that at deposition time of 7 h the intensity peak of [110] plane strongly decreased and seems that the [210] plane peak is the preferred orientation at this condition. Present paper deals with studies of the antibacterial activity of different synthesized samples after 24 h in the presence of Escherichia coli and Staphylococcus aureus cells. It is found that the growth time has an essential role in the morphology and antibacterial properties of TiO2 nanostructures.

Thermal stability and spectroscopic properties of Fe3BO6 of small crystallites with a bonded carbon surface layer

Abstract A well-known canted antiferromagnetic Fe3BO6 with functionalized properties is an important material useful for light energy carrier, electrodes, gas sensors, and biological probes. In this investigation, a facile synthesis is explored in order to obtain Fe3BO6 of small crystallites in a specific shape of nanoplates by self-combustion method. To access (i) whether Fe3BO6 is formed at the as-prepared stage and (ii) how it stands stable with a residual carbon surface layer, thermal gravimetric (TG) analysis has been carried out by heating 10–20 mg powder (as-prepared) at a typical 10 K/min heating rate over 300–1100 K under air or argon atmosphere. The electronic absorption, infrared (IR) and Raman spectra studied for the Fe3BO6 sample in this investigation elucidate how the density of states of the phonons and valence electrons confine in small crystallites. IR and Raman bands in the oxygen polygons also confer the results of forming Fe3BO6 with a bonded surface carbon layer. A stable bonded surface layer supports thermal stability of small crystallites and it affects other useful functional properties.

Sensitivity Study of Nanocrystalline Fe3BO6 Sensor for Methane Gas Detection

The iron borate Fe3BO6 with functionalized properties in a nanostructure is an important material useful for electrodes, gas sensors, and biological probes. In this paper, we studied the X-ray diffraction pattern, field-emission electron microscopy, and methane (CH4) gas sensing properties of synthesized Fe3BO6 nanocrystallites in a shape of nanoplates and nanobars from an iron borate glass 40Fe2O3-60B2O3 by annealing it in microwave for 15 min at 823 and 1023 K, respectively, in air. The temperature dependent sensitivity for CH4 (1000 ppm) illustrates a maximum value of 43% at an operating temperature 525 K for the 1023 K annealed sample. The sensitivity is found to be varied from 9% to 39% when the CH4 gas concentration is increased from 50 to 1000 ppm. Thus, the sample has a reasonably good sensitivity for methane. Furthermore, the sensor exhibits fast response (~1 min) and a good recovery time (~1.6 min) as compared with other oxide materials.

Ultrasound-assisted preparation of a nanostructured zinc(II) amine pillar metal-organic framework as a potential sorbent for 2,4-dichlorophenol adsorption from aqueous solution

Using a green and simple route with ultrasound illumination under atmospheric pressure and at room temperature, the nanosized preparation of a Zn(II) metal-organic framework, [Zn(ATA)(BPD)]∞ (ATA = 2‐aminoterephthalic acid), BPD = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), having nano-plate shape and 3D channel framework, was considered and the product was named as compound 1. The X-ray diffraction (XRD), scanning electron microscopy (SEM), IR spectroscopy, Brunauer–Emmett–Teller (BET), and thermogravimetric analysis (TGA) were used for characterization of the synthesized micro/nano-structures. Further, impact of different sonication times and initial reagent contents on the shape and size of the micro/nano-structures was investigated. The results show that under ultrasound irradiation non-aggregated plates with uniform morphology can be obtained with content of [0.0125] M of the initial reagents in the presence of triethylamine (TEA) at 120 min. Moreover, through N2 adsorption, effect of the preparation route on the porosity was explored. The bulk and nano-plates of compound 1 were also studied for adsorption of 2,4-dichlorophenol as a pollutant sample. Kinetic studies indicated that 2,4-dichlorophenol adsorption via MOF nano-plates are of first-order kinetics. Also, MOF nano-plates have significantly been reutilized for five times while their adsorption properties have remained unchanged.

Fabrication of DSSC with Nanostructured ZnO Photo Anode and Natural Dye Sensitizer

This paper is intended to enhance the efficiency of ZnO and mixed natural dye based DSSC. Nanostructured ZnO is synthesized through chemical bath deposition technique. The FESEM image of ZnO shows 3D structure with two types of morphology, nano-rod and nano-plate shape. The average length of ZnO nano-rod is 5 µm and diameter is 200 nm. The natural dyes, extracted from fresh purple cabbage and beet root and their mixed counterpart are used as a photo-sensitizer for fabrication of DSSCs. The UV-vis absorption spectra are used to identify the characteristic absorption peaks of these extracted natural dyes and their mixed counterpart. The mixed dye shows wider absorption spectra over the individual dyes. A reduced DRS of mixed dye is seen due to higher light absorbance. The performances of the fabricated DSSCs are compared and it shows that mixed dye has better performance (0.3824%) over the individuals.

Unravelling kinetic and thermodynamic effects on the growth of gold nanoplates by liquid transmission electron microscopy.

The growth of colloidal nanoparticles is simultaneously driven by kinetic and thermodynamic effects that are difficult to distinguish. We have exploited in situ scanning transmission electron microscopy in liquid to study the growth of Au nanoplates by radiolysis and unravel the mechanisms influencing their formation and shape. The electron dose provides a straightforward control of the growth rate that allows quantifying the kinetic effects on the planar nanoparticles formation. Indeed, we demonstrate that the surface-reaction rate per unit area has the same dose-rate dependent behavior than the concentration of reducing agents in the liquid cell. Interestingly, we also determine a critical supply rate of gold monomers for nanoparticle faceting, corresponding to three layers per second, above which the formation of nanoplates is not possible because the growth is then dominated by kinetic effects. At lower electron dose, the growth is driven by thermodynamic and the formation and shape of nanoplates are directly related to the twin-planes formed during the growth.

Unprecedented high photocatalytic activity of nanocrystalline WO3/NiWO4 hetero-junction towards dye degradation: Effect of template and synthesis conditions

Nanocrystalline NiWO4 wolframite structure has been prepared by a simple salt solution addition (NiW1SS), co-precipitation (NiW4Cop) and sol–gel (NiW4SG) techniques via employing polymeric templates particularly polyethylene glycol (PEG) and triblock copolymer, respectively. The synthesis method as well as the metal molar ratio (W/Ni) influenced the phases, morphology, optical and surface properties of synthesized samples as configured by X-ray diffraction, transmission electron microscopy, UV–vis diffuse reflectance spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy and N2 sorptiometry techniques. Accordingly, the NiW1SS material that exposed only NiWO4 of nano-plate shape at a molar ratio (W/Ni) 1 indicates higher surface texturing values (SBET=52.6m2/g, Vp=0.2061cm3/g and r=15.7nm) exceeding those of NiW4Cop (SBET=15.07m2/g, Vp=0.0491cm3/g and r=13.0nm) of anisotropic shapes (hexagonal and tetragonal); synthesized at a ratio of 4 and by the same template (PEG). The NiW1SS material indicated Eg value of 2.23eV whereas that of NiW4Cop revealed a value of 2.92eV. On the other hand, NiW4SG that exposed well crystallized WO3 beside NiWO4 of nano-flakes shape and an average diameter of 25nm indicates Eg value of 2.56eV and in addition evokes the formation of narrow pore size distribution in mesopores range (2–12nm) as well as in macropores (60nm) exploring the effect of template type on the pore texturing. Photodegradation of methylene blue (MB) dye was used to evaluate the photoactivity of NiWO4 catalysts under UV irradiations. The NiW4SG catalyst exhibited the best degradation performance (92.5% for MB after 5h). The results showed that the feasibility of MB degradation was not only due to morphological properties but also to the NiWO4/WO3 heterojunction. Significantly, WO3 facilitates effective charge separation as traced by the photoluminescence emission spectra.

Facile Preparation of Mn3O4 Hausmanite Nanoplates from a New Octahedral Manganese (III) Schiff Base Complex

A novel bidentate Schiff base ligand L (L = N-(4-amino-2-chloro-phenyl)-2-hydroxybenzaldehyde) and the subsequent octahedral manganese(III) Schiff base complex MnL3 have been synthesized and characterized by, FT-IR spectroscopy and elemental analyses (CHN). Additionally, Schiff base ligand has been characterized by 1H NMR spectroscopy. Thermogravimetric analysis of the ligand and its metal complexes reveals their thermal stability and decomposition pattern. Thus, the MnL3 complex has been investigated as a novel precursor for the facile preparation of Mn3O4 nanoparticles via solid-state thermal decomposition under aerobic conditions, at a temperature of ca. 450 °C The resulting Mn3O4 nanocrystals were characterized by FT-IR spectroscopy, X-ray powder diffraction (XRPD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The XRPD studies reveal the characteristic diffraction peaks indexed to the Mn3O4 hausmanite structure, while the absence of additional peaks tends to clearly indicate the high purity of the sample. In addition, the TEM/SEM investigations displayed the nanoplate shape of the rather monodisperse crystalline Mn3O4 nanoparticles, with an average diameter of ca. 10 nm. The statistical distribution of the nanoparticles size has to be provided with an histogram graphic.

Simple route to bismuth titanate from bismuth glycolate precursor via sol–gel process

Bismuth titanate (Bi4Ti3O12) is successfully synthesised using bismuth glycolate as a bismuth source and acetic acid and ethanol as solvents via sol–gel process without adding a complexing agent. The synthesis parameters investigated are acetic acid to ethanol ratio, mechanical stirring time, calcination time and temperature. It is found that an increase in the acetic acid to ethanol ratio causes an increase in the gelation time, and the calcination temperature is the key factor in transformation to a crystalline Bi4Ti3O12 perovskite phase. The perovskite phase of Bi4Ti3O12 in a nanoplate shape is obtained after stirring the precursor mixture solution containing 0·1 acetic acid to ethanol ratio for 1 h at room temperature, followed by calcination of the dried gel at 600°C for 1 h.