Band 116, Heft 5

Piezoelectric materials, traditionally recognized for their intriguing electrical properties, have recently emerged as promising candidates in catalysis. This shift in focus stems from their ability to generate electrical charges in response to mechanical stress, which imparts distinct advantages for catalytic applications. This study explores the growing body of research highlighting the catalytic potential of piezoelectric materials, emphasizing their unique properties that set them apart from conventional catalysts. Piezoelectric catalysts offer a novel approach to catalysis by exploiting their polarization - induced surface reactivity. The polarization in these materials can influence adsorption energies, reaction pathways, and kinetics, thereby influencing catalytic activity. This paper delves into the fundamental principles governing the catalytic behaviour of piezoelectric, presenting key experimental findings and theoretical insights. Here, emphasis is given to the catalytic property of piezoelectric in carbon dioxide photoreduction. Furthermore, we have discussed the challenges and opportunities of employing piezoelectric materials as catalysts. This paper provides a comprehensive overview of the current state of knowledge in this emerging field, highlighting the potential applications and outlining the key challenges that researchers face in harnessing the catalytic prowess of piezoelectric materials. As the understanding of these materials continues to deepen, the integration of piezoelectric catalysts into practical applications may significantly impact various industries, ushering in a new era of efficient and tailored catalytic processes.

The growing demand for sustainable and eco-friendly energy storage technologies has spurred extensive research into novel materials for batteries. This review investigates alternatives to traditional batteries that use synthetic polymers, such as polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), and polypropylene (PP), which often involve hazardous materials and significant environmental impact. It focuses on cellulose, a biopolymer derived from renewable sources, and its derivative, nanocellulose, as promising, eco-friendly alternatives for various battery components. Cellulose, a biopolymer derived from renewable sources, has emerged as a promising candidate due to its abundant availability, low cost, and inherent eco-friendliness. Cellulose is greatly used in development of polymer electrolyte, anode, and cathode materials, acts as binder or additives and as a separator. These uses are discussed, showcasing their electrochemical performance, capacity retention, and rate capability. Nanocellulose, with its nanoscale porosity and mechanical stability, is shown to be a promising separator material, enhancing ion transport, and improving battery cyclability. Moreover, potential modifications and optimization strategies to improve battery performance have been discussed. Despite their potential advantages, cellulose-based batteries are still in the research and development stage. Several challenges must be addressed, including manufacturing scalability, optimizing energy density, and achieving high power outputs. However, ongoing research and advancements in polymer electrolyte materials bring us closer to commercialising these promising battery technologies. Cellulose-based batteries offer reduced environmental impact throughout their life cycle, from sourcing to disposal, contributing to a greener and more circular economy. In conclusion, cellulose-based batteries demonstrate great promise as an environmentally friendly and sustainable energy storage solution. This review aims to provide concise and insightful information on cellulose’s application in different components of batteries, showcasing its potential to transform the energy storage landscape and contribute to a cleaner and more sustainable future.

In the present article, we have prepared Bi 1- x La x FeO 3 ( x = 0.00, 0.10 and 0.15) nanoparticles through the sol–gel method. These nanoparticles were composited on high-quality reduced graphene oxide (rGO) sheets via ultrasonication followed by stirring processes. All the prepared materials were subjected to various structural, micro-structural and optical characterization techniques. X-ray diffraction, transmission electron microscopy, and ultraviolet–visible spectroscopy were used for structural, microstructural, and optical studies, respectively. Scanning electron microscopy micrograph coupled with energy dispersive X-ray analysis was used to confirm the formation of nanocomposite. Photocatalytic properties and dye degradation efficiency of as prepared materials were tested under the irradiation of UV–Vis light of intensity one sun and air mass coefficient 1.5. We have used UV–Vis spectrophotometer for the measurement of concentration of rhodamine dye. The dye degradation efficiency of Bi 0.85 Sm 0.15 FeO 3 –reduced graphene oxide (BFO-15@GR) was found to be better than other prepared materials. Our research indicates that the BFO-15@GR composite is the best material, as it degraded 81 % of the dye after 120 min of radiation.

Due to its multiferroic properties and narrow optical bandgap, BiFeO 3 has been widely explored for spintronics, photovoltaics, and photocatalysis applications. Using various synthesis techniques, BiFeO 3 can be synthesized in various forms, such as bulk, thin films, and nanostructures. It is challenging to synthesize the pure BiFeO 3 phase due to the volatile nature of bismuth and the very narrow temperature range for forming this phase. So, this work aims to synthesize the pure BiFeO 3 phase at lower annealing temperatures using an efficient sol–gel method. We have chosen the annealing temperature from 450 °C to 650 °C, and a detailed analysis of structural and optical properties is performed here. X-ray diffraction is used to confirm the crystalline nature of the material. A single-phase Rietveld analysis of X-ray diffraction patterns is carried out to study the effect of annealing temperature on structural parameters. All the samples are crystalized in pure rhombohedral BiFeO 3 phase with the R 3 c space group symmetry, except those annealed at higher temperatures, 600 °C and 650 °C. Strain and dislocation densities were decreasing with an increase in the annealing temperature. From the UV–visible analysis, a strong response is observed below 600 nm in the visible region, and the band gap from the absorption behaviour is estimated in the range of 2.26–2.60 eV for these bismuth ferrite nanoparticles. Fourier transform infrared analysis confirmed the existence of metal–oxygen bonds in bismuth ferrite nanoparticles. These nanoparticles were found to be thermally stable based on the thermal analysis performed using differential scanning calorimetry. Bismuth ferrite nanoparticles were weakly magnetic based on the vibrating sample magnetometry analysis.

Carbon-based perovskite solar cells present an attractive option for large-scale production due to their notable stability and cost-effectiveness. Streamlining the architecture of perovskite solar cells and eliminating the hole transport layer contribute to additional cost savings. Hole transport layer free perovskite solar cells are more efficient to fabricate than regular perovskite solar cells making them a strong candidate for advancing large-scale production processes. Despite the enhanced stability of double perovskite solar cells, their efficiency remains lower than that of single perovskite cells. In response to environmental concerns, efforts are underway to develop lead-free perovskite absorber layers, with Cs 2 AgBiBr 6 identified as a promising candidate. In experimental studies, Cs 2 AgBiBr 6 double perovskite solar cell had achieved a low band-gap ( E g = 1.64 eV) through hydrogenation treatment, it shows potential for further research and development. To enhance the performance of this double perovskite solar cell, we have excluded the hole transport layer and opted for carbon as a back electrode. Utilizing SCAPS-1D simulation software, we conducted optimizations, including selecting an appropriate transparent conducting oxide and electron transport layer, adjusting the absorber layer thickness, optimizing acceptor density, modulating the doping density and defect density in the absorber layer, and optimizing the work function of the front electrode. These optimizations resulted in improved efficacy, with the fluorine doped tin oxide/tungsten oxide Cs 2 AgBiBr 6 /Carbon configuration demonstrating exceptional photovoltaic performance, featuring open-circuit voltage = 1.41 V, short-circuit current density = 21.95 mA cm −2 , power conversion efficiency = 25.28 %, and fill factor = 81.54 %.

In this work, we have utilized four different equations of states (EOSs), in particular the modified Lenard Jones EOS, Birch–Murnaghan EOS, Vinet–Rydberg EOS and Thomsen EOS, which depend on various central ideas to compute the pressure dependent properties of TiO 2 for anatase and rutile phases. We found that the modified Lenard Jones EOS is generally reasonable to work out pressure dependent properties of TiO 2 (rutile stage) while every one of these situations of state are similarly appropriate to compute compression at high pressure for TiO 2 (rutile stage). We further found the modified Lenard Jones EOS is more steady to compute the Gruneisen parameter for both rutile phase and anatase phase since this EOS gives practically predictable values of the Gruneisen parameter as pressure increments and the diagram plotted between Gruneisen parameter and volume pressure proportion is additionally a straight line.

In this paper, we report a novel method, namely the exploding wire technique, to synthesize tin nanoparticles, utilizing tin wire and plate. The prepared colloidal suspension of silvery-black colour, was centrifuged. The nanoparticles collected after centrifugation were collected, dried and subjected to further grinding to finally obtain the powder nanoparticles. X-ray diffraction analysis reveals tetragonal crystal structure of Sn nanoparticles having lattice parameters a = b = 5.8238 Å and c = 3.1806 Å. The crystallite sizes within the 35–69 nm range were determined through the Debye–Scherrer relation and Williamson–Hall analysis. However, much smaller size Sn nanoparticles of 5–16 nm were observed through field emission scanning electron microscopy, energy dispersive spectroscopy and elemental mapping analyses. The crystal volume and strain were calculated and differential scanning calorimetry measurements determined the reduced value of melting temperature for prepared Sn nanoparticles. The optical processes occurring in prepared nanoparticles were probed with the help of ultraviolet–visible spectroscopy and photoluminescence spectroscopies. Furthermore, Fourier transform infrared spectroscopic studies could identify the functional groups/bondings present in the prepared nanoparticles.

We have studied the impact of nanowire curviness on the percolation threshold and the effective resistance ( R eff ) of two-dimensional films with their application as transparent electrodes. We have generated highly conductive zero-width curvy nanowires as one-dimensional rods on the non-conducting substrate. The resistivity of the network is found using the percolation theory. The length ( l ref ) of a nanowire is assumed to be constant i.e. 1 unit whereas the system length is varied from 16 to 64 units. The maximum angle of curvatures ( θ c ) of a nanowire is considered in our computations to quantify the degree of curviness. We have used two different methods to generate curvy nanowires. We have found that as the system length decreases, the effective resistance also decreases. It is also observed that the R eff of the network at fixed system lengths is slightly more for higher angles of curvature of a nanowire. It can be said that curviness in nanowires is not desirable for randomly oriented systems as it doesn’t affect the conductivity of networks much. Our results also show that the effect of curvature on transmittance depends on how the curvy nanowire is generated. We have also investigated the impact of length dispersity on the nanowire-based network by introducing longer-length curvy wires in the system. The incorporation of bidisperse distribution in length seems to improve the performance of these networks in terms of electrical and optical properties. Our work can be extended to any network, nanocomposites, and films with fillers such as nanowires or nanorods.

Mustard husk (MSH) can be used as an efficient alternative for energy storage applications and fuels. The synthesis of MSH is done by varying three crucial parameters during microwave pyrolysis. The effect of these process parameters (microwave power, radiation time and flow rate of nitrogen gas) on mustard husk char yield and Brunauer–Emmett–Teller (BET) surface area has been accomplished. The synthesized mustard husk char yield tends to decrease on increasing microwave power, radiation time and flow rate of nitrogen gas. BET surface area of mustard husk char increases with each pyrolysis parameter and after attaining a maximum value it decreases. In the operational window of microwave power (700–1300 W), radiation time (20–50 min) and flow rate (25–175 ml min −1 ), the yield decreased by 50.27 %, 34.29 % and 21.08 % of its initial value, respectively. BET surface area of synthesized char at microwave power of 1000 W increases to 121.23 % while it increases to 113.83 % and 109.57 % at radiation time 35 min and flow rate 100 ml min −1 , respectively. Characterization of mustard husk using thermogravimetric analysis and differential thermogravimetry shows that the mustard husk is thermally stable up to 236 °C and most of the volatile materials get liberated from mustard husk at 89.87 %. Fourier transform infrared spectroscopy of mustard husk was also carried out to extract information about the various functional groups associated with it.

Polymers enriched with reactive sites and free-charge clouds have been a considerable field of research. The present study reports the nonlinear optical activity of polymer 4-amino-6-chloro-1,3-benzenedisulfonamide using density functional theory. The substitution of the sulfonamide group on the symmetrical positions gave rise to the intramolecular charge transfer within the title molecule. The molecular electrostatic potential surface illustrates that the O=S=O and NH 2 groups act as electrophilic and nucleophilic groups and were found responsible for the intramolecular charge transfer. This gave the dipole moment of 5.4 Debye for the title molecule. The molecular orbitals were used to compute the band gap of 3.81 eV. The value of hyperpolarizability was computed as 499.22 au. This value was found 27 times higher than the general reference nonlinear optical activity compound urea (18.53 au), four times higher than thiourea (102.3 au), and two times higher than phenyl urea (245.69 au). Thus, the reported study validates that the title molecule can be used as a potential NLO material.

The increasing production of protein-rich waste, primarily from the household and food industries, associated with the growing global population has imposed a negative environmental burden on society at large. Protein waste is a growing international concern, with more unsegregated waste released from developing countries. This work explored the sorption behavior of amorphous plant extract of Humulus lupulus , towards bovine serum albumin as a representative model protein. The adsorbed proteins analyzed using scanning electron microscopy, revealed irregular beads masking the surface cues and changing the surface smoothness, further validated by atomic force microscopy. The atomic force microscopy analysis showed an increase in the surface potential of pre-adsorbed material (−60.2 mV to 42.5 mV) compared to post-adsorbed complex (−736 mV to 640 mV) suggesting the protein interaction on the plant surface. Differential scanning calorimetry indicated the possible interaction between protein and surface which is responsible for showing a shift in the enthalpy pattern of the surface pre- and post-adsorption. Change in enthalpy pattern, higher surface potential, and shift in Fourier-transform infrared spectroscopy binding pattern indicates an interaction between plant surface and protein that was further validated and confirmed using the adsorption isotherm. The adsorption isotherm towards bovine serum albumin protein followed the Freundlich isotherm with k and n values of 1.143 and 1.157, respectively. The Freundlich isotherm pattern observed for the material has suggested H. lupulus plant extract as a suitable surface for protein adsorption. The study opens the avenue for the adsorption kinetics of different proteins and establishing the plant extract as a suitable remediation solution for environmental sustainability.