Interfacial band offset engineering with barium-doping towards enhanced performance of all inorganic CsPbI2Br perovskite solar cells.

This study investigates the incorporation of Ba2+ at a low concentration into CsPbI2Br, resulting in the formation of mixed CsPb1-xBaxI2Br perovskite films. Photovoltaic devices utilizing these Ba-doped CsPbI2Br (Ba-CsPbI2Br) perovskite films achieved a higher stabilized power conversion efficiency of 14.07% compared to 11.60% for pure CsPbI2Br films. First-principles density functional theory calculations indicate that the improved device performance can be attributed to the efficient transport of conduction electrons across the interface between Ba-CsPbI2Br and the TiO2 electron transporting layer (ETL). The Ba-CsPbI2Br/TiO2 interface exhibits a type-II staggered band alignment with a smaller conduction band offset (CBO) of 0.25 eV, in contrast to the CsPbI2Br/TiO2 interface with a CBO of 0.48 eV. The reduced CBO at the Ba-CsPbI2Br/TiO2 interface diminishes the barrier for conduction electrons to transfer from the Ba-CsPbI2Br layer to the TiO2 layer, facilitating efficient charge transport.

Recent trends in the nanozeolites-based oxygen concentrators and their application in respiratory disorders.

Medical-grade oxygen is the basic need for all medical complications, especially in respiratory-based discomforts. There was a drastic increase in the demand for medical-grade oxygen during the current pandemic. The non-availability of medical-grade oxygen led to several complications, including death. The oxygen concentrator was only the last hope for the patient during COVID-19 pandemic around the globe. The demands also are everlasting during other microbial respiratory infections. The yield of oxygen using conventional molecular zeolites in the traditional oxygen concentrator process is less than the yield noticed when its nano-form is used. Nanotechnology has enlightened hope for the efficient production of oxygen by such oxygen concentrators. Here in the current review work, the authors have highlighted the basic structural features of oxygen concentrators along with the current working principle. Besides, it has been tried to bridge the gap between conventional oxygen concentrators and advanced ones by using nanotechnology. Nanoparticles being usually within 100 nm in size have a high surface area to volume ratio, which makes them suitable adsorbents for oxygen. Here authors have suggested the use of nano zeolite in place of molecular zeolites in the oxygen concentrator for efficient delivery of oxygen by the oxygen concentrators.

Nanostructured Antibiotics and Their Emerging Medicinal Applications: An Overview of Nanoantibiotics.

Bacterial strains resistant to antimicrobial treatments, such as antibiotics, have emerged as serious clinical problems, necessitating the development of novel bactericidal materials. Nanostructures with particle sizes ranging from 1 to 100 nanometers have appeared recently as novel antibacterial agents, which are also known as "nanoantibiotics". Nanomaterials have been shown to exert greater antibacterial effects on Gram-positive and Gram-negative bacteria across several studies. Antibacterial nanofilms for medical implants and restorative matters to prevent bacterial harm and antibacterial vaccinations to control bacterial infections are examples of nanoparticle applications in the biomedical sectors. The development of unique nanostructures, such as nanocrystals and nanostructured materials, is an exciting step in alternative efforts to manage microorganisms because these materials provide disrupted antibacterial effects, including better biocompatibility, as opposed to minor molecular antimicrobial systems, which have short-term functions and are poisonous. Although the mechanism of action of nanoparticles (NPs) is unknown, scientific suggestions include the oxidative-reductive phenomenon, reactive ionic metals, and reactive oxygen species (ROS). Many synchronized gene transformations in the same bacterial cell are essential for antibacterial resistance to emerge; thus, bacterial cells find it difficult to build resistance to nanoparticles. Therefore, nanomaterials are considered as advanced solution tools for the fields of medical science and allied health science. The current review emphasizes the importance of nanoparticles and various nanosized materials as antimicrobial agents based on their size, nature, etc.

Health and Environmental Risks of Incense Smoke: Mechanistic Insights and Cumulative Evidence.

Incense burning is practiced alongside many sacred rituals across different regions of the world. Invariable constituents of incense brands are 21% (by weight) herbal and wood powder, 33% bamboo stick, 35% fragrance material, and 11% adhesive powder. Major incense-combustion outputs include particulate matter (PM), volatile organic content, and polyaromatic hydrocarbons. The relative toxicity of these products is an implicit function of particle size and incomplete combustion, which in turn vary for a specific incense brand. Lately, the attention given to the Air Quality Index by international regulatory bodies has created concern about mounting PM toxicity. The uncharacteristically small physical dimensions of these entities complicates their detection, and with no effect of gravity PM fractions rapidly contribute to oxidative stress, enhancing random biochemical reactions upon being inhaled. Incense burning generates four times the PM extent (45 mg•g-1) of cigarettes (~10 mg•g-1). Several poisonous gases, such as CO, CO2, NO2, and SO2, and the unavoidable challenge of disposing of the burnt incense ash further add to the toxicity. Taken together, these issues demonstrate that incense burning warrants prompt attention. The aim of this article is to highlight the toxicity of incense-combustion materials on the environment and human health. This discussion could be significant in framing future policy regarding ecofriendly incense manufacture and reduced usage.

Enriched Catalytic Activity of TiO2 Nanoparticles Supported by Activated Carbon for Noxious Pollutant Elimination.

Cleaning wastewater has become one of the most serious issues for a number of scientists and researchers in recent years, as water is the most basic need for the daily life of humans. There has been a focus on the removal of noxious pollutants from wastewater effluents by using nanocatalysts owing to their unique physicochemical actions and stability. Herein we manufactured TiO2 nanoparticles supported by activated carbon (AC-TiO2) using a cost-effective sonochemical method. The band structures of the AC-TiO2 and TiO2 were modified from 3.2 to 3.1 eV, thus increasing the catalytic activity. The structural, optical and anatase crystal phase properties, with morphological confirmation, were studied by applying UV-DRS, PL, FESEM, XRD, along with HRTEM, respectively. The specific surface area, calculated by BET analysis, was found to be ~241 m2/gm and ~46 m2/gm for AC-TiO2 and TiO2. The degradation efficiency of the as-prepared nanocatalysts against the very toxic but rarely studied organic textile dye pollutant RO 84 was investigated and 97% efficiency were found for the AC-TiO2 as compared to pure TiO2, which is a highly appreciated finding in the catalytic dye degradation application domain. Such surface-modified nanocatalysts could be further implemented for the treatment of wastewaters/waste effluents released from chemical industries, laboratories and other sources.

Variations and similarities in structural, chemical, and elemental properties on the ashes derived from the coal due to their combustion in open and controlled manner.

Coal fly ash (CFA) and coal-based incense sticks ash (ISA) have several similarities and differences due to the presence of coal as a common component in both of them. CFA are produced from the combustion of pulverized coal during electricity production in the thermal power plants while ISA are produced from the burning of incense sticks at religious places and at houses. A typical black colored Indian, incense sticks are mainly are comprised of coal powder or potassium nitrate, wood chip, fragrance, binder or binding agent, and bamboo sticks. The black colored incense sticks have coal powder or charcoal as a facilitator for smoother burning of incense sticks. The detailed investigation of CFA and ISA by X-ray fluorescence spectroscopy (XRF), electron diffraction spectroscopy (EDS), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), Fourier transform-infrared (FTIR), X-ray diffraction (XRD), particle size analyzer (PSA), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) revealed the morphological, chemical, and elemental properties. Both the coal based ashes comprises minerals like calcites, silicates, ferrous, alumina, and traces of Mg, Na, K, P, Ti, and numerous toxic heavy metals as confirmed by the XRF, ICP-AES, and EDS. While, microscopy revealed the presence of well-organized spherical shaped particles, namely cenospheres, plerospheres, and ferrospheres of size varying from 0.02 µm to 7 microns in CFA. Whereas, ISA particles are irregular, aggregated, calcium to carbon rich whose size varies from 60 nm to 9 microns and absence of well-organized spherical structures. The well developed and crystalline structure in CFA is due to the controlled combustion parameter in thermal power plants during the burning of coal while incense sticks (IS) burning is under uncontrolled manner. So, FTIR and XRD confirmed that the major portion of fly ash constitutes crystalline minerals whereas ISA have mainly amorphous phase minerals. CFA have ferrospheres of both rough and smooth surfaced, which was absent from the ISA and hence ferrous particles of CFA are of high magnetic strength. The detailed investigation of ashes will lead to the applications of ashes in new fields, which will minimize the solid waste pollution in the environment.

Thermodynamically induced in Situ and Tunable Cu Plasmonic Behaviour.

The Cu nanoparticles (Cu NPs) were grown in soda-lime glass matrix through Cu+ ↔ Na+ ion exchange methods under thermal annealing in an open environment and studied variation in their size on tunable plasmonic behaviour, optical absorption spectra and photoluminescence (PL). A blue shift from 570 to 560 nm was observed in localized surface plasmon resonance (SPR) of Cu NPs from 550 to 650 °C. A mutual relation between size and surface plasmon resonance with full width half maxima (FWHM) has been derived for plasmonic properties at variable temperatures. Structural investigations of embedded Cu NPs have been confirmed by using HRTEM and EDX. Grazing incidence X-ray diffraction (GIXRD) had identified a crystalline nature of Cu NPs under annealed conditions. XPS, Raman and secondary ion mass spectroscopies (SIMS) have identified an embedding behaviour of Cu NPs in glass matrix. Plasmonic and thermodynamic properties of embedded Cu NPs have explained their in situ thermal growth mechanism for efficient distribution where enthalpy (∆H), entropy (∆S) and Gibbs free energy (∆G) have interpreted their temperature driven Cu NPs growth. An interdependence of ∆H, ∆S and ∆G has been developed vis-a-vis activation energy on an extent of 12.54 J/mol.

In Situ Growth of Low-Dimensional Silver Nanoclusters with Their Tunable Plasmonic and Thermodynamic Behavior.

Optical properties of noble metal nanostructures associated with localized surface plasmon resonance (SPR) are technically important for optical switches and plasmonic devices. In this work, silver nanoclusters are embedded inside the soda-lime glass matrix, followed by a thermal annealing process in an open air atmosphere for 1 h. The effects of thermal annealing on the plasmonic behavior of Ag nanoclusters embedded in the glass matrix are studied with UV-vis spectroscopy and photoluminescence. In the SPR spectra, a 14 nm blue shift is observed in the visible range under the influence of thermal annealing at a higher temperature. The thermal effects on Ag particle size and SPR have been illustrated for plasmonic properties. The structural and elemental investigation of as-grown Ag nanoclusters is confirmed by X-ray diffraction, high-resolution transmission electron microscope, and X-ray photoelectron spectroscopy. The structural, plasmonic, and thermodynamic properties associated with the growth mechanism of Ag nanoclusters have been explained under the thermal process. Enthalpy (ΔH), entropy (ΔS), and Gibbs energy (ΔG) for Ag nanoclusters growth and nucleation are significantly calculated and interpreted at different temperatures. An empirical relation among the ΔH, ΔS, and ΔG is developed vis-a-vis activation energy (97.70 J/mol), which is calculated by the Arrhenius linear equation.

In Situ Free Radical Growth Mechanism of Platinum Nanoparticles by Microwave Irradiation and Electrocatalytic Properties.

Microwave irradiation was employed for spherical-shaped platinum nanoparticle (Pt NPs) preparation. Spherical Pt NPs indexed with (111) facets were prepared using Pt(II) precursor salt, glycerol as solvent and reducing agent, and polyvinylpyrrolidone (PVP) as a shape directer under microwave irradiation for 3-5 min at 300 °C. Electron spin resonance (ESR) peak at 336.000 mT (milli Tesla) confirmed the free radical formation from aqueous glycerol solution which acted as reducing species under microwave. The 2-8-nm diameter of particles was obtained by high-resolution transmission electron microscope. Dynamic light scattering was used to optimize the microwave dose followed by 33 and 48 nm size and 51 and 67 mV zeta potential of Pt NPs, respectively. The PVP was demonstrated as shape controlling agent investigated by Fourier transmission infrared spectroscopy (FTIR). The electrocatalytic performance of as-prepared Pt colloids was investigated using cyclic voltammetry which showed a higher catalytic activity for ethanol redox reaction.