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The higher amount of Pt usage and its poisoning in methanol oxidation reaction in acidic media is a major setback for methanol fuel cells. Herein, a promising dual application high-performance electrocatalyst has been developed for hydrogen evolution and methanol oxidation. A low Pt-content nanoalloy co-doped with Cu, Mn, and P is synthesized using a modified solvothermal process. Initially, ultrasmall ≈2.9 nm PtCuMnP nanoalloy is prepared on N-doped graphene-oxide support and subsequently, it is characterized using several analytical techniques and examined through electrochemical tests. Electrochemical results show that PtCuMnP/N-rGO has a low overpotential of 6.5 mV at 10 mA cm -2 in 0.3 m H 2 SO 4 and high mass activity for the hydrogen evolution reaction. For the methanol oxidation reaction, the PtCuMnP/N-rGO electrocatalyst exhibits robust performance. The mass activity of PtCuMnP/N-rGO is 6.790 mA mg -1 Pt , which is 7.43 times higher than that of commercial Pt/C (20% Pt). Moreover, in the chronoamperometry test, PtCuMnP/N-rGO shows exceptionally good stability and retains 72% of the initial current density even after 20,000 cycles. Furthermore, the PtCuMnP/N-rGO electrocatalyst exhibits outstanding performance for hydrogen evolution and methanol oxidation along with excellent anti-poisoning ability. Hence, the developed bifunctional electrocatalyst can be used efficiently for hydrogen evolution and methanol oxidation., (© 2024 Wiley‐VCH GmbH.)

The selection and design of new electrode materials for energy conversion and storage are critical for improved performance, cost reduction, and mass manufacturing. A bifunctional anode with high catalytic activity and extended cycle stability is crucial for rechargeable lithium-ion batteries and direct borohydride fuel cells. Herein, a high entropy novel three-dimensional structured electrode with Pr-doped hollow NiFeP nanoflowers inlaid on N-rGO was prepared via a simple hydrothermal and self-assembly process. For optimization of Pr content, three (0.1, 0.5, and 0.8) different doping ratios were investigated. A lithium-ion battery assembled with NiPr 0.5 FeP/N-rGO electrode achieved an outstanding specific capacity of 1.61 Ah g -1 at 0.2 A g -1 after 100 cycles with 99.3 % Coulombic efficiencies. A prolonged cycling stability of 1.02 Ah g -1 was maintained even after 1000 cycles at 0.5 A g -1 . In addition, a full cell battery with NiPr 0.5 FeP/N-rGO∥LCO (Lithium cobalt oxide) delivered a promising cycling performance of 0.52 Ah g -1 after 200 cycles at 0.15 A g -1 . Subsequently, the NiPr 0.5 FeP/N-rGO electrode in a direct borohydride fuel cell showed the highest peak power density of 93.70 mW cm -2 at 60 °C. Therefore, this work can be extended to develop advanced electrode for next-generation energy storage and conversion systems., (© 2023 Wiley-VCH GmbH.)

The study was carried out to compare the in vitro and in vivo heat shock responses of cattle and buffaloes. The expression of heat responsive genes (HSP70 and HSF family) were studied in vitro in peripheral blood mononuclear cells (PBMCs) of cattle and buffalo. In vivo observations on animals were carried out to investigate the physiological responses of cattle and buffalo at different THI over a period of 14 months. The study indicated that onset and severity of heat stress at different THI varied significantly between cattle and buffalo. Rectal temperature (RT) showed a significant (p < 0.05) increase at THI 67 in buffaloes and at THI 68 in cattle. Significant (p < 0.01) differences in RT between the species were observed at THI 71, 72, and 73. Respiration rate (RR) significantly (p < 0.05) increased at THI 70 in both the species and significant (p < 0.05) differences in RR were observed between the species at THI 65, 68, 69, and 74. THI had significant (p < 0.05) effect on blood glucose and blood electrolytes of the species with increased levels at higher THI. Serum AST and ALT levels showed less pronounced changes over increasing THI. Heat stress-associated expressions of HSP 70 genes followed temporal changes with incremental THI. The expression of HSPA8 was consistent at lower THI whereas upregulation of HSPA1A and HSPA1L was evident at higher THI. The study concludes that changes in physiological parameters such as RT and RR occur in a phasic pattern in both species and onset of heat stress was early in buffalo as compared to cattle., (© 2023. The Author(s) under exclusive licence to International Society of Biometeorology.)

Halogen bonding triggered by the Lewis basic nature of acetonitrile catalyzes the site-selective C-3 triaryl methylation of indoles and N -triaryl methylation of imidazoles with trityl chlorides under catalyst-, metal-, and additive-free conditions at room temperature. This method generates a quaternary carbon centre appended to a heterocyclic moiety. UV-Vis and FT-IR analyses indicate the existence of halogen bonding which is the driving force of the reaction. This approach is suitable for a wide range of substrates, furnishing moderate to excellent yields (up to 100%) of triaryl methylated products under ambient reaction conditions. Equimolar amounts of reactants are sufficient to obtain the optimum yield and in some cases pure products can be obtained without column chromatography.

Quantum chemical calculations have been carried out to investigate the hydrogen storage capacity of Be 2 (NLi) 2 cluster. Calculations reveal that the cluster can take up to eight H 2 molecules reaching a maximum gravimetric density of 21.04 wt%. Six H 2 molecules bind at the Li atoms and two H 2 bind at the Be atoms with moderate binding energy which is required for reversible storage of H 2 . Symmetry-adapted perturbation analysis reveals the significant contribution of electrostatic and induction and very minor contribution of dispersion toward the total interaction energy. Molecular dynamics simulations reveal that the H 2 molecules are strongly bound at 77 K and get slowly released at elevated temperatures., (© 2022 Wiley Periodicals LLC.)

Methylene blue is a dye that is extensively used in the textile industry but it is a hazardous, carcinogenic, and mutagenic pollutant. Therefore, the treatment of wastewater containing methylene blue by photocatalytic degradation under visible light without using any sacrificial agent (H 2 O 2 ) is an important method towards attaining an eco-friendly environment. Herein, the nanocomposite of Ag-doped TiO 2 on WO 3 nanoparticles (Ag@TiO 2 /WO 3 ) was prepared by a modified sol-gel precipitation route, and their physicochemical properties were studied. The bandgap of Ag sensitized metal oxide nanocomposite in Ag@TiO 2 /WO 3 was slightly reduced compared to the pristine titania due to the creation of interstitial energy states during colligation of titania and tungsten oxide. The ease of charge carrier transfers through the heterojunction of TiO 2 /WO 3 increased the photocatalytic activity of the photocatalyst. Furthermore, in Ag@TiO 2 /WO 3 the plasmonic Ag sensitization to the host semiconductor TiO 2 has further boosted the rate of photocatalytic degradation because of the surface plasmon resonance (SPR) and hindrance of charge carrier recombination. Due to the synergistic effect of SPR and the presence of heterojunction in Ag@TiO 2 /WO 3 , the photocatalytic activity was found to be 25 times higher for Ag@TiO 2 /WO 3 than that of commercial DP25 photocatalyst under visible light towards methylene blue degradation., (Copyright © 2021 Elsevier Ltd. All rights reserved.)