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To attain a comfortable building interior, building windows play a crucial role. Because of the transparent nature of the window, it allows heat loss and gain and daylight. Thus, they are one of the most crucial parts of the building envelope that have a significant contribution to the overall building energy consumption. The presence of dust particles on a window can change the entering light spectrum and creates viewing issues. Thus, self-cleaning glazing is now one of the most interesting research topics. However, aside from the self-cleaning properties, there are other properties that are nominated as glazing factors and are imperative for considering self-cleaning glazing materials. In this work, for the first time, Hf-doped ZnO was investigated as self-cleaning glazing and its glazing factors were evaluated. These outcomes show that the various percentages of ZnO doping with Hf improved the glazing factors, making it a suitable glazing candidate for the cold-dominated climate. [ABSTRACT FROM AUTHOR]

Five different rare‐earth‐based nanocrystalline high entropy oxides (HEOs) with fluorite structure and average crystallite sizes between 6 and 8 nm are prepared and their photocatalytic behavior toward azo dye degradation and photoelectrochemical water splitting for hydrogen generation is examined. The cationic site in the fluorite lattice consists of five equimolar elements selected from the group of rare‐earth elements including La, Ce, Pr, Eu, and Gd and second‐row transition metals, Y and Zr. The studied HEOs exhibit bandgaps in the range from 1.91 to 3.0 eV and appropriate valence and conduction bands for water splitting. They reveal high photocatalytic activity that is mostly attributed to the accessibility of more photocatalytic active sites, which provide radicals responsible for the azo dye degradation. The materials successfully produce hydrogen by photocatalytic water splitting, suggesting the potential of HEOs as new photocatalysts. The photocatalytic performances of all studied HEOs outperform the single fluorite oxides or equivalent mixed oxides. The Ce0.2Zr0.2La0.2Pr0.2Y0.2O2 (CZLPY) engender hydrogen in 9.2 µmol mg−1 per hour that is much higher content than for pristine CeO2 material which amounts to 0.8 µmol mg−1 per hour. [ABSTRACT FROM AUTHOR]

In this paper, for the first time, electroactivated disposable pencil graphite electrode (ePGE) was used for the detection of bioflavonoid hesperidin with cyclic and differential pulse voltammetry. The electroactivation efficiency of the pencil graphite electrode (PGE) was examined employing electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM) and the enhancement of electron transfer kinetics of the PGE after the electroactivation was found. Hesperidin is irreversibly oxidized on the ePGE and its oxidation was the most pronounced at pH=5.0. Two electrode processes were detected, on one hand, a mixed diffusion and adsorption control was observed for the first electrode process. On the other hand, only diffusion control was observed in the second electrode process. Linear dependence between the peak current and the hesperidin concentration was obtained in the concentration range from 5×10−7 mol dm−3 to 1×10−5 mol dm−3 and the determined lower limit of detection (LOD) was 2×10−7 mol dm−3. Moreover, hesperidin in pharmaceutical formulation (containing active substance, hesperidin, and excipients) was quantified using ePGE. A good correlation was obtained between experimentally obtained hesperidin concentration by voltammetric analysis and concentration determined by standard HPLC technique (R2=0.9462). [ABSTRACT FROM AUTHOR]

In this study, we synthesized nanostructured zinc oxide (ZnO) by using various concentrations (0–0.05 M) of cetyltrimethylammonium bromide (CTAB) as a surfactant to optimize its morphology for gas sensor applications. The optimization process was used to elucidate the morphology effects (rod-shaped and flower-shaped morphologies). The morphologies were investigated through scanning electron microscopy, in which the assembly of nanorods leading to a spherical microstructure with a CTAB concentration of 0.005 M was observed. Brunauer–Emmett–Teller isotherm measurements revealed a surface area of 7.928 g/m2 for the flower-like morphology, which was relatively higher than those of other CTAB-assisted morphologies. Such morphological features were expected to contribute toward high-performance gas-sensing. The effect of morphology variation on the resistance of ZnO microstructures was used for gas measurements. Among the varied morphologies, a sample with a spherical flower-shaped morphology exhibited a very high response at low temperatures (~29 at 25 °C) toward NO X gas (0.75 ppm) and a high selectivity toward NO x among ammonia (NH 3), toluene (C 6 H 5 CH 3), carbon monoxide (CO), acetone (CH 3 COCH 3), and ethanol (C 2 H 5 OH). Raman and photoluminescence spectroscopy analyses unraveled the presence of a high density of oxygen vacancies in the sample, thereby suggesting a close link between the defective nature of the sample and the high response of the flower-like ZnO at low temperatures. Development of selective and sensitive ZnO-based NO X gas sensors operating at low temperatures.Synthesis of spherical flower-shaped ZnO with CTAB as the sensing material.Excellent sensitivity of 29 toward NO X at 25 °C.Low concentration (0.19–0.74 ppm) detection of NO X at 25 °C. Highly selectivity toward NO X among NH 3 , C 6 H 5 CH 3 , CO, CH 3 COCH 3 , and C 2 H 5 OH at 25 °C. Image 1 [ABSTRACT FROM AUTHOR]

The photovoltaic (PV) system is one of the most promising technologies that generate benevolent electricity. Therefore, fossil fuel-generated electric power plants, that emit an enormous amount of greenhouse gases, can be replaced by the PV power plant. However, due to its lower efficiency than a traditional power plant, and to generate equal amount of power, a large land area is required for the PV power plant. Also, transmission and distribution losses are intricate issues for PV power plants. Therefore, the inclusion of PV into a building is one of the holistic approaches which reduce the necessity for such large land areas. Building-integrated and building attached/applied are the two types where PV can be included in the building. Building applied/attached PV(BAPV) indicates that the PV system is added/attached or applied to a building, whereas, building integrated PV (BIPV) illustrates the concept of replacing the traditional building envelop, such as window, wall, roof by PV. In India, applying PV on a building is growing due to India's solar mission target for 2022. In 2015, through Jawaharlal Nehru National Solar Mission, India targeted to achieve 100 GW PV power of which 40 GW will be acquired from roof-integrated PV by 2022. By the end of December 2019, India achieved 33.7 GW total installed PV power. Also, green/zero energy/and sustainable buildings are gaining significance in India due to rapid urbanization. However, BIPV system is rarely used in India which is likely due to a lack of government support and public awareness. This work reviewed the status of BIPV/BAPV system in India. The BIPV window system can probably be the suitable BIPV product for Indian context to reduce the building's HVAC load. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) ReS2 is considered as a promising energy storage material owing to its high theoretical capacity and extremely weak van der Waals forces. However, the use of 2D ReS2 is limited by its low electrical conductivity, slow ion diffusion, and huge volume expansion. Herein, we demonstrate oxygen incorporation and interlayer expansion of ReS2 nanosheets deposited on hollow mesoporous carbon spheres. The oxygen content of 2D ReS2 is controlled by varying the reaction solvents and temperatures and thus, its interlayer spacing is expanded, which facilitates the redox kinetics by means of the improved electronic conductivity and rapid ion diffusion as demonstrated by computational calculation and electrochemical characterization. Moreover, a hollow mesoporous core/shell hybrid architecture contributes to a large accessible area and porous channels. The as-optimized hybrid electrodes with expanded interlayers and oxygen content achieve higher capacity and better rate and cycling capabilities than other samples. Therefore, this chemical strategy highlights the importance of controlling the interlayer spacing and chemistry of ReS2 to overcome the kinetic and stability limitations of 2D energy storage nanomaterials. [ABSTRACT FROM AUTHOR]

Building consumes fossil fuel generated electricity to satisfy its air condition, heating and artificial lighting load demand. Offsetting this building energy demand by employing energy efficient advanced switchable smart windows are possible. Currently, electrically actuated switchable smart window systems include electrochromic (EC), suspended particle device (SPD) and liquid crystal (LC). EC works under direct current (DC) power supply while SPD and LC need alternating current (AC) power supply. In this work, details (working principle, window parameters and building energy saving potential) of these three window technologies have been reviewed. Highly insulated switchable smart window and powering them employing PV system is also an attractive strategy. However, smart windows need stakeholder support particularly from government and building regulation code for its smooth penetration to the building sector. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) water splitting is one of the promising, environmentally friendly, carbon emission-free strategies for the cost-effective production of hydrogen. The interest in developing effective approaches for solar-to-hydrogen production with stable and visible light active semiconductors directed many researchers to develop stable and efficient materials. For the first time, a nanostructured TiVO 4 photoanode was fabricated at a substrate temperature of 250 °C and further annealed at 600 °C using the spray pyrolysis technique and it obtained an optical band gap of ∼2.18 eV. The photoanode underwent photoelectrochemical testing, where it exhibited a high photocurrent density of 0.080 mA cm -2 at 1.23 V ( vs. reversible hydrogen electrode), which can be stable up to 110 min. Further, various physicochemical characterizations were employed to understand the phase purity and thin film growth mechanism. A systematic substrate and annealed temperatures were monitored during the fabrication process. The transmission electron microscopy (TEM) studies revealed agglomeration of TiVO 4 nanoparticles with an average size of ∼100 nm accompanying dendritic orientation at the outer edge. This study envisages the design and development of a novel photocatalyst for water splitting under visible light irradiation, an ideal route to a cost-effective, large-scale, sustainable route for hydrogen production., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Green hydrogen production is one of the most desirable sustainable goals of the United Nations. Thus, for that purpose, we developed hematite (α-Fe 2 O 3 ), an n-type semiconductor, a desirable candidate for photoelectrochemical (PEC) water splitting, enabling hydrogen evolution. High recombination losses, low efficiency, and large-scale production hinder its potential. To address these issues, we have fabricated optimized bare and cadmium oxide (CdO)-decorated hematite thin film nanorod arrays using a throughput radio frequency (RF) sputtering with efficient water splitting behavior. To the best of our knowledge, no work has been done so far on the synthesis of CdO/α-Fe 2 O 3 via RF sputtering for PEC application. Bare α-Fe 2 O 3 samples, with a morphology of vertically aligned nanorods, were fabricated with optimized parameters such as as-deposited 70 nm of Fe, an angle of deposition of 70°, and an annealing temperature of 600 °C, which showed a photocurrent density of 0.38 mA/cm 2 at 1.65 V vs reversible hydrogen electrode (RHE). Characterizations depicted that this unique morphology with high crystallinity directly enhanced the performance of hematite photoanodes. Further, deposition of 30 nm of cadmium (CdO) on the α-Fe 2 O 3 nanorods produced a corn-like morphology with CdO nanoparticles (∼2 nm), resulting in 4-times enhancement of the PEC performance (1.2 mA/cm 2 at 1.65 V vs RHE). CdO acted as a co-catalyst, responsible for satisfactory suppression of recombination and facilitating the hole transfer, directly enhancing the overall photocurrent density. This photoanode showed an extremely stable behavior over a period of 26 h when kept under constant illumination. Furthermore, the CdO-modified photoanode showed a better dye degradation (98% in 40 min) than the bare hematite (60% in 40 min), proving to be an efficient photoanode., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Substitutional doping and different nanostructures of ZnO have rendered it an effective sensor for the detection of volatile organic compounds in real-time atmosphere. However, the low selectivity of ZnO sensors limits their applications. Herein, hafnium (Hf)-doped ZnO (Hf-ZnO) nanostructures are developed by the hydrothermal method for high selectivity of hazardous NO X gas in the atmosphere, substantially portraying the role of doping concentration on the enhancement of structural, optical, and sensing behavior. ZnO microspheres with 5% Hf doping showed excellent sensing and detected 22 parts per billion (ppb) NO X gas in the atmosphere, within 24 s, which is much faster than ZnO (90 s), and rendered superior sensing ability ( S = 67) at a low temperature (100 °C) compared to ZnO ( S = 40). The sensor revealed exceptional stability under humid air ( S = 55 at 70% RH), suggesting a potential of 5% Hf-ZnO as a new stable sensing material. Density functional theory (DFT) and other characterization analyses revealed that the high sensing activity of 5% Hf-ZnO is attributed to the accessibility of more adsorption sites arising due to charge distortion, increased oxygen vacancies concentration, Lewis acid base, porous morphology, small particle size (5 nm), and strong bond interaction amidst NO 2 molecule with ZnO-Hf-O vacancy sites, resulting from the substitution of the host cation (Zn 2+ ) with doping cation (Hf 4+ )., Competing Interests: The authors declare no competing financial interest., (© 2022 American Chemical Society.)

Doping plays a significant role in affecting the physical and chemical properties of two-dimensional (2D) dichalcogenide materials. Controllable doping is one of the major factors in the modification of the electronic and mechanical properties of 2D materials. MoS 2 2D materials have gained significant attention in gas sensing owing to their high surface-to-volume ratio. However, low response and recovery time hinder their application in practical gas sensors. Herein, we report the enhanced gas response and recovery of Nb-doped MoS 2 gas sensor synthesized through physical vapor deposition (PVD) toward NO 2 at different temperatures. The electronic states of MoS 2 and Nb-doped MOS 2 monolayers grown by PVD were analyzed based on their work functions. Doping with Nb increases the work function of MoS 2 and its electronic properties. The Nb-doped MoS 2 showed an ultrafast response and recovery time of t rec = 30/85 s toward 5 ppm of NO 2 at their optimal operating temperature (100 °C). The experimental results complement the electron difference density functional theory calculation, showing both physisorption and chemisorption of NO 2 gas molecules on niobium substitution doping in MoS 2 ., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Transparent, superhydrophilic materials are indispensable for their self-cleaning function, which has become an increasingly popular research topic, particularly in photovoltaic (PV) applications. Here, we report hydrophilic and superhydrophilic ZnO by varying the morphology for use as a self-cleaning coating for PV applications. Three different ZnO microstructures, such as ZnO nanorods (R-ZnO), ZnO microflowers (F-ZnO), and ZnO microspheres (M-ZnO), were developed by hydrothermal methods. The surface morphology by using X-ray diffraction (XRD), wettability behavior by using water contact angle (WCA) measurements, structural and optical properties by using photoluminescence (PL), Raman, and UV-vis spectrophotometry, and defect estimation by using X-ray photoelectron spectroscopy (XPS) of the ZnO nanostructured films were systematically investigated. XRD confirmed the formation of the hexagonal wurtzite structure of ZnO. The average crystallite sizes of prepared R-ZnO, F-ZnO, and M-ZnO were found to be 28.95, 11.19, and 41.5 nm, respectively. The band gap values of ZnO nanostructures were calculated from the UV-vis absorption spectrum and found to be 3.6, 3.3, and 3.1 eV for R-ZnO, F-ZnO, and M-ZnO, respectively. The WCAs for R-ZnO and F-ZnO were 20.2 and 11.19°, respectively, while M-ZnO behaved like a superhydrophilic material having a WCA of 2.8°., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)