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•A straightforward sonochemical synthesis of MoO3-g-C3N4 photocatalyst leads enhanced hydrogen generation and environmental remediation.•The solar-driven water-splitting exhibited ...higher photocurrent ∼ 7.5 mA/cm2 for hydrogen generation in 0.5 M Na2SO4 electrolyte at pH = 7.•Methylene blue is photo catalytically decomposed beyond 92% under 1 SUN visible light irradiation by MoO3-g-C3N4.•The synergistic effect of MoO3 and g-C3N4 leads to fast separation of the light-induced charge carriers, resulting in significant improvement in photocatalysis.
An ultrasonic fabrication of MoO3-g-C3N4 photocatalyst for substantially better photocatalytic recital is presented. XRD and FTIR confirmed the orthorhombic phase of MoO3-g-C3N4. The SEM manifests the oblate-like structure of g-C3N4 and nano rod-like morphology for MoO3 and MoO3-g-C3N4, respectively. The photocatalytic properties are evaluated by photoelectrochemical (PEC) and photodegradation measurements under visible light. The linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) comprehend MoO3-g-C3N4 as a hydrogen evolution photocatalyst. The photocurrent density of MoO3-g-C3N4 is recorded beyond 7.5 mA/cm2, which is approximately 5–6 folds greater than pure MoO3 and g-C3N4. In addition, the visible light exposure showed MoO3-g-C3N4 photocatalyst could decompose methylene blue (MB) dye up to 93%. The efficient separation and transfer of charges allocated to MoO3-g-C3N4 follow Z-scheme and pseudo-first-order kinetic reaction. The creation of heterojunctions among g-C3N4 and MoO3 suppresses the unfavorable electron-hole pairs recombination process and therefore recesses charge transfer resistance, hence augmenting photocatalytic performance.
Herein, the synthesis, characterization, and photoelectrochemical and photocatalytic characteristics of hydrothermally prepared La2O3–g-C3N4, CoO–g-C3N4, and La2O3–CoO–g-C3N4 are discussed. The XRD ...analysis and crystalline phases unveiled the impregnation of La2O3 and CoO into g-C3N4. The microscopic analysis supports the formation of g-C3N4 nanoflakes and La2O3 and CoO nanoparticles embedded homogeneously in the La2O3–CoO–g-C3N4 nanocomposite, whereas the EDX comprehended their respective elemental composition and ratios. A bandgap energy of 2.38 eV for La2O3–CoO–g-C3N4 was calculated using the Tauc plot method, complementing high visible-light activity. The solar-driven water-splitting reaction exhibited significant photocurrent efficiency (~3.75 mA/cm2), augmenting the hydrogen generation by La2O3–CoO–g-C3N4 compared to that by pure g-C3N4, La2O3–g-C3N4, and CoO–g-C3N4 in 0.5 M Na2SO4 electrolyte. The synergistic effect of La2O3 and CoO impregnation with g-C3N4 led to effective division of the photogenerated charge transporters, enhancing the photocatalytic hydrogen generation by the photocatalysts. Furthermore, photocatalytic pollutant removal, namely greater than 90% decomposition of methylene blue (MB) from water, was investigated with a pseudo-first-order reaction kinetics under 1 sun visible-light irradiation. Thus, La2O3–CoO–g-C3N4 nanocomposite was found to be a prospective material for harnessing solar energy.
Molybdenum (Mo) impregnated g-C3N4 (Mo-CN) nanotubes are fabricated via a thermal/hydrothermal process to augment photoelectrochemical properties during solar-driven water-splitting (SDWS) reactions. ...Graphitic-C3N4 is an attractive material for photocatalysis because of its suitable band energy, high thermal and chemical stability. The FE-SEM and HR-TEM comprehend the nanotube-like morphology of Mo-CN. The spectroscopic characterization revealed bandgap energy of 2.63 eV with high visible-light activity. The x-ray diffraction of pristine g-C3N4 and Mo-CN nanotubes discloses the formation of triazine-based nanocrystalline g-C3N4, which remains stable during hydrothermal impregnation of Mo. Furthermore, Mo-CN nanotubes possess high sp2-hybridized nitrogen content, and metallic/oxidized Mo nanoparticles (in a ratio of 1:2) are impregnated into g-C3N4. The XPS analysis confirms C, N, and Mo for known atomic and oxidation states in Mo-CN. Furthermore, high photocurrent efficiency (~ 5.5 mA/cm2) is observed from 5%-Mo-CN nanotubes. That displays efficient SDWS by 5%-Mo-CN nanotubes than other counterparts. Impedance spectroscopy illustrated the lowest charge transfer resistance (Rct) of 5%-Mo-CN nanotubes, which further confirms the fast electron transfer kinetics and efficient charge separation resulting in high photocurrent generation. Hence, 5%Mo-CN composite nanotubes can serve as a potential photocatalytic material for viable solar-driven water splitting.
•Surface acoustic wave (SAW) sensors for detection of organic vapors are presented.•A variety of materials used as vapor recognition layers on SAW devices are reviewed.•Limitations and challenges of ...SAW organic vapor sensors are discussed.•The directions for future exploratory research in SAW vapor sensors are identified.
The necessity of selectively detecting various organic vapors is primitive not only with respect to regular environmental and industrial hazard monitoring, but also in detecting explosives to combat terrorism and for defense applications. Today, the huge arsenal of micro-sensors has revolutionized the traditional methods of analysis by, e.g. replacing expensive laboratory equipment, and has made the remote screening of atmospheric threats possible. Surface acoustic wave (SAW) sensors – based on piezoelectric crystal resonators – are extremely sensitive to even very small perturbations in the external atmosphere, because the energy associated with the acoustic waves is confined to the crystal surface. Combined with suitably designed molecular recognition materials SAW devices could develop into highly selective and fast responsive miniaturized sensors, which are capable of continuously monitoring a specific organic gas, preferably in the sub-ppm regime. For this purpose, different types of recognition layers ranging from nanostructured metal oxides and carbons to pristine or molecularly imprinted polymers and self-assembled monolayers have been applied in the past decade. We present a critical review of the recent developments in nano- and micro-engineered synthetic recognition materials predominantly used for SAW-based organic vapor sensors. Besides highlighting their potential to realize real-time vapor sensing, their limitations and future perspectives are also discussed.
The potent HIV-1 capsid inhibitor GS-6207 is an investigational principal component of long-acting antiretroviral therapy. We found that GS-6207 inhibits HIV-1 by stabilizing and thereby preventing ...functional disassembly of the capsid shell in infected cells. X-ray crystallography, cryo-electron microscopy, and hydrogen-deuterium exchange experiments revealed that GS-6207 tightly binds two adjoining capsid subunits and promotes distal intra- and inter-hexamer interactions that stabilize the curved capsid lattice. In addition, GS-6207 interferes with capsid binding to the cellular HIV-1 cofactors Nup153 and CPSF6 that mediate viral nuclear import and direct integration into gene-rich regions of chromatin. These findings elucidate structural insights into the multimodal, potent antiviral activity of GS-6207 and provide a means for rationally developing second-generation therapies.
A facile fabrication of MoOxSy-CoPI photocatalyst revealed a conformal growth of nanoflowers. The photoelectrochemical studies exhibited significantly enhanced photocurrents with a stable and ...repeatable photocurrent response under visible light (1SUN) simulated solar irradiation.
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•Facile synthesis of Molybdenum oxysulphide-cobalt phosphate (MoOxSy-CoPi) novel material for solar water splitting.•The MoOxSy-CoPI photocatalyst corresponded to the most stable oxidation states of Mo, Co, S, P, and O in the composite.•Nanoflowers of MoOxSy-CoPI showed controlled thickness up to ∼10 nm, and variable interspaces of 200-400 nm were produced.•Band-gap energy of 2.44 eV and significantly higher (7-8 folds) photocurrent density of MoOxSy-CoPI is recorded compared to MoOxSy and CoPI.
Hydrogen is considered as a clean alternative green energy future fuel. Since the Honda-Fujishima effect for photoelectrochemical water splitting is known, there has been a substantial boost in this field. Numerous photocatalysts based on metals, semiconductors, and organic-inorganic hybrid-systems have been proposed. Several factors limit their efficiency, e.g., a stable PEC-WS setup, absorbing visible light, well-aligned band energy for charge transfer, electrons and holes, and their separation to avoid recombination and limited water redox reactions. Metallic doping and impregnation of stable and efficient co-catalysts such as Pt, Ag, and Au showed enhanced PEC-WS. We used Cobalt-based co-catalyst with molybdenum oxysulfide photocatalyst for effectual solar-driven water splitting.
To develop photocatalysts for efficient PEC processes capable of absorbing sufficient visible light, good band energy for effective charge transfer, inexpensive, significant solar-to-chemical energy conversion efficiencies. Above all, it is developing such PEC-WS systems that will be commercially viable for renewable energy resources.
We prepared Molybdenum oxysulphide-cobalt phosphate photocatalyst for PEC-WS through a facile hydrothermal route using ammonium heptamolybdate, thiourea, and metallic Cobalt precursors.
An effectual photocatalyst is produced for solar-driven water splitting. The conformal morphology of MoOxSy-CoPi nanoflowers is a significant feature, as observed under FE-SEM and HR-TEM. XRD confirmed the degree of purity and orthorhombic crystal structure of MoOxSy-CoPi. EDX and XPS identify the elemental compositions and corresponding oxidation states of each atom. A 2.44 eV band-gap energy is calculated for MoOxSy-CoPi from the diffused reflectance spectrum. Photo- Electrochemical Studies (PEC) under 1-SUN solar irradiation revealed 7-8 folds enhanced photocurrent (∼ 3.5 mA/cm2) generated from MoOxSy-CoPi/FTO in comparison to Co-PI/FTO (∼ 0.5 mA/cm2) and MoOxSy-/FTO respectively, within 0.5 M Na2SO4 electrolyte (@pH=7) and standard three electrodes electrochemical cell.
Our results showed MoOxSy-CoPi as promising photocatalyst material for improved solar-driven photoelectrochemical water splitting system.
This research article describes the synthesis of hetero-structured WO3/BiVO4 nanoflakes as photoanode material for photoelectrochemical water splitting. The heterojunction WO3/BiVO4 nanoflakes ...developed by facile hydrothermal method. WO3/BiVO4 uniform films fabricated simply by drop casting technique onto indium oxide tin oxide (ITO) coated glass substrates. Detailed morphological, structural and compositional characterization of WO3/BiVO4 carried out by XRD, FE-SEM, and EDX techniques. Optical properties studied by Raman and UV–VIS spectroscopy, respectively. The band gap energy of WO3/BiVO4 hetero-junction estimated to be about 2.00 eV. These WO3/BiVO4 heterojunction structures offered enhanced photo-conversion efficiency and increased photo-corrosion stability. In addition, these nanoflakes films showed significantly enhanced photo-electrochemical properties due to their high surface-area and enhanced separation of the photo-generated charge at the WO3/BiVO4 interface. The effect of calcination temperature on WO3/BiVO4 also investigated.
•WO3/BiVO4 nanoflakes as photoanode materials were synthesized via hydrothermal method.•The photoelectrochemical performance of WO3/BiVO4 nanoflakes was investigated.•Photocurrent density generated by WO3/BiVO4 nanoflakes (0.109 mA/cm2).•WO3/BiVO4 heterojunction structure enhances charge-carrier separation.
We assume a modified (conformal) gravity theory, which produces a stronger interaction at large scale, in order to discuss the statistical distribution of the galaxy clusters based on thermodynamics. ...We develop
N
-body partition function and exploit it to study the equations of state of the system. The probability distribution function is deduced from the partition function taking the modified gravity theory into account. We compare the theoretical model with the data available through SDSS (III) via its 12th data release.
Pathogenesis related (PR) proteins are one of the major sources of plant derived allergens. These proteins are induced by the plants as a defense response system in stress conditions like microbial ...and insect infections, wounding, exposure to harsh chemicals, and atmospheric conditions. However, some plant tissues that are more exposed to environmental conditions like UV irradiation and insect or fungal attacks express these proteins constitutively. These proteins are mostly resistant to proteases and most of them show considerable stability at low pH. Many of these plant pathogenesis related proteins are found to act as food allergens, latex allergens, and pollen allergens. Proteins having similar amino acid sequences among the members of PR proteins may be responsible for cross-reactivity among allergens from diverse plants. This review analyzes the different pathogenesis related protein families that have been reported as allergens. Proteins of these families have been characterized in regard to their biological functions, amino acid sequence, and cross-reactivity. The three-dimensional structures of some of these allergens have also been evaluated to elucidate the antigenic determinants of these molecules and to explain the cross-reactivity among the various allergens.
Herein, hydrothermal fabrication of CdO-g-C3N4 photocatalyst for a substantially better photocatalytic recital in water splitting is presented. The XRD analysis confirms the cubic phase of ...CdO-g-C3N4, whereas FTIR and UV-VIS studies revealed the presence of respective groups and a median band gap energy (2.55 eV) of the photocatalyst, respectively, which further enhanced its photo-electrochemical (PEC) properties. The SEM displays the oblong structures of g-C3N4 sheets and nano rod-like morphology of CdO and CdO-g-C3N4, respectively. The HR-TEM exhibits morphology & orientation of the grains and substantiates the polycrystal-line nature of CdO-g-C3N4 nanocomposite. The photocatalytic water-splitting concert is evaluated by PEC experiments under 1 SUN visible light irradiation. Linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) comprehend the CdO-g-C3N4 as a hydrogen evolution photocatalyst. A photocurrent density beyond ≥5 mA/cm2 is recorded from CdO-g-C3N4, which is 5–6 folds greater than pure CdO and g-C3N4. The efficient separation and transfer of charges allocated to CdO-g-C3N4 and fabricating heterojunctions between g-C3N4 and CdO suppresses the unfavorable electron-hole pairs recombination process. Thus, it recesses charge transfer resistance, augmenting enhanced photocatalytic performance under 1 SUN irradiation.
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