Ultrasonic-Assisted Conversion of Micrometer-Sized BiI3 into BiOI Nanoflakes for Photocatalytic Applications.

This work describes a novel method for converting bismuth triiodide (BiI3) microplates into bismuth oxyiodide (BiOI) nanoflakes under ultrasonic irradiation. To produce BiOI nanoflakes with a high yield and high purity, the conversion process was carefully adjusted. Rapid reaction kinetics and increased mass transfer are benefits of the ultrasonic-assisted approach that result in well-defined converted BiOI nanostructures with superior characteristics. The produced BiOI nanoflakes were examined utilizing a range of analytical methods, such as Transmission Electron Microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The progress in the ultrasonic conversion process with time was monitored through diffuse reflectance spectroscopy (DRS). The outcomes demonstrated the effective conversion of BiI3 microplates into crystalline, homogeneous, high-surface-area BiOI nanoflakes. Additionally, the degradation of organic dyes (methylene blue) under ultraviolet (UV) light irradiation was used to assess the photocatalytic efficacy of the produced BiOI nanoflakes. Because of their distinct morphology and electrical structure, the BiOI nanoflakes remarkably demonstrated remarkable photocatalytic activity, outperforming traditional photocatalysts. The ability of BiOI nanoflakes to effectively separate and utilize visible light photons makes them a viable option for environmental remediation applications. This work not only shows the promise of BiOI nanoflakes for sustainable photocatalytic applications but also demonstrates a simple and scalable approach to their manufacturing. The knowledge gathered from this work opens up new avenues for investigating ultrasonic-assisted techniques for creating sophisticated nanomaterials with customized characteristics for a range of technological uses.

Impact of Annealing in Various Atmospheres on Characteristics of Tin-Doped Indium Oxide Layers towards Thermoelectric Applications.

The aim of this work was to investigate the possibility of modifying the physical properties of indium tin oxide (ITO) layers by annealing them in different atmospheres and temperatures. Samples were annealed in vacuum, air, oxygen, nitrogen, carbon dioxide and a mixture of nitrogen with hydrogen (NHM) at temperatures from 200 °C to 400 °C. Annealing impact on the crystal structure, optical, electrical, thermal and thermoelectric properties was examined. It has been found from XRD measurements that for samples annealed in air, nitrogen and NHM at 400 °C, the In2O3/In4Sn3O12 share ratio decreased, resulting in a significant increase of the In4Sn3O12 phase. The annealing at the highest temperature in air and nitrogen resulted in larger grains and the mean grain size increase, while vacuum, NHM and carbon dioxide atmospheres caused the decrease in the mean grain size. The post-processing in vacuum and oxidizing atmospheres effected in a drop in optical bandgap and poor electrical properties. The carbon dioxide seems to be an optimal atmosphere to obtain good TE generator parameters-high ZT. The general conclusion is that annealing in different atmospheres allows for controlled changes in the structure and physical properties of ITO layers.

Catalytic polymer nanocomposites for environmental remediation of wastewater.

The removal of harmful chemicals and species from water, soil, and air is a major challenge in environmental remediation, and a wide range of materials have been studied in this regard. To identify the optimal material for particular applications, research is still ongoing. Polymer nanocomposites (PNCs), which combine the benefits of nanoparticles with polymers, an alternative to conventional materials, may open up new possibilities to overcome this difficulty. They have remarkable mechanical capabilities and compatibility due to their polymer matrix with a very high surface area to volume ratio brought about by their special physical and chemical properties, and the extremely reactive surfaces of the nanofillers. Composites also provide a viable answer to the separation and reuse problems that hinder nanoparticles in routine use. Understanding these PNCs materials in depth and using them in practical environmental applications is still in the early stages of development. The review article demonstrates a crisp introduction to the PNCs with their advantageous properties as a catalyst in environmental remediation. It also provides a comprehensive explanation of the design procedure and synthesis methods for fabricating PNCs and examines in depth the design methods, principles, and design techniques that guide proper design. Current developments in the use of polymer nanocomposites for the pollutant treatment using three commonly used catalytic processes (catalytic and redox degradation, electrocatalytic degradation, and biocatalytic degradation) are demonstrated in detail. Additionally, significant advances in research on the aforementioned catalytic process and the mechanism by which contaminants are degraded are also amply illustrated. Finally, there is a summary of the research challenges and future prospects of catalytic PNCs in environmental remediation.

SbI3·3S8: A Novel Promising Inorganic Adducts Crystal for Second Harmonic Generation.

In the past twenty years, the basic investigation of innovative Non-Linear Optical (NLO) crystals has received significant attention, which has built the crucial heritage for the use of NLO materials. Fundamental research is essential given the scarcity of materials for NLO compounds, especially in the deep ultraviolet (DUV) and middle- and far-infrared (MFIR) regions. In the present work, we synthesized high-quality MFIR SbI3·3S8 NLO crystals having a length in the range of 1-5 mm through rapid facile liquid phase ultrasonic reaction followed by the assistance of instantaneous natural evaporation phenomenon of the solvent at room temperature. X-ray diffraction (XRD) results ratify the hexagonal R3m structure of SbI3·3S8 crystal, and energy-dispersive X-ray spectroscopy (EDX) demonstrates that the elemental composition of SbI3·3S8 crystal is similar to that of its theoretical composition. The direct and indirect forbidden energy gaps of SbI3·3S8 were measured from the optical transmittance spectra and they were shown to be 2.893 eV and 1.986 eV, respectively. The green sparkling signal has been observed from the crystal during the second harmonic generation (SHG) experiment. Therefore, as inorganic adducts are often explored as NLO crystals, this work on the MFIR SbI3·3S8 NLO crystal can bring about additional investigations on this hot topic in the near future.

Nanogenerator for determination of acoustic power in ultrasonic reactors.

This paper presents the novel use of a sonochemical reaction product as a sensing material in self-powered ultrasonic reactor devices for determination of ultrasound parameters. A piezoelectric nanogenerator was fabricated via sonochemical synthesis of SbSeI nanowires compressed into a bulk sample. The prepared device was used to develop two fast and simple evaluation methods for acoustic power in liquid. A calibration procedure was carried out for both methods using a VCX-750 ultrasonic processor. The ultrasound acoustic power was varied within a 150 W to 750 W range and the corresponding nanogenerator electrical responses were measured. The voltage signals of the first method fit the best with theoretical dependence. The second technique was based on the application of the Fast Fourier Transform (FFT) to the measured electric output. The results of these two approaches were convergent. Acoustic power values of 255(8) W and 222(7) W were determined for the Sonic-6 reactor using theoretical dependence fitting to experimental data and FFT analysis, respectively. Developed sensing technology possesses great potential for sonochemistry applications.

Assessment of the Piezoelectric Response of an Epoxy Resin/SbSINanowires Composite Filling FDM Printed Grid.

This paper shows a piezoelectric response from an innovative sensor obtained by casting epoxy-SbSI (antimony sulfoiodide) nanowires nanocomposite to a grid structure printed using a fuse deposition modeling (FDM) method. The grid is shown to be a support structure for the nanocomposite. The applied design approach prospectively enables the formation of sensors with a wide spectrum of shapes and a wide applicability. The voltage signal obtained as a result of the piezoelectric effect reached 1.5V and 0.5V under a maximum static stress of 8.5 MPa and under a maximum dynamic stress of 22.3 kPa, respectively. These values are sufficient for potential application in sensor systems. The effect of a systematic increase in the voltage signal with subsequent cycles was also observed, which similarly allows the use of these sensors in monitoring systems for structures exposed to unfavorable cyclical loads. The obtained results also show that the piezoelectric signal improves with increase in strain rate.

Contactless photomagnetoelectric investigations of 2D semiconductors.

Background: Applications of two-dimensional (2D) materials in electronic devices require the development of appropriate measuring methods for determining their typical semiconductor parameters, i.e., mobility and carrier lifetime. Among these methods, contactless techniques and mobility extraction methods based on field-effect measurements are of great importance. Results: Here we show a contactless method for determining these parameters in 2D semiconductors that is based on the photomagnetoelectric (PME) effect (also known as the photoelectromagnetic effect). We present calculated dependences of the PME magnetic moment, evoked in 2D Corbino configuration, on the magnetic field as well as on the intensity and spatial distribution of illumination. The theoretical predictions agree with the results of the contactless investigations performed on non-suspended single-layer graphene. We use the contactless PME method for determining the dependence of carrier mobility on the concentration of electrons and holes induced by a back-gate voltage. Conclusion: The presented contactless PME method, used in Corbino geometry, is complementary to the mobility extraction methods based on field-effect measurements. It can be used for determining the mobility and diffusion length of carriers in different 2D materials.