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Oxide-based solid electrolytes are gaining popularity among researchers owing to their great structural stability. In this work, a novel oxide-based ternary composite (AlPO4-SiO2-Li4P2O7) electrolyte is synthesized via a conventional solid-state process with excellent water stability and high ionic conductivity. The crystallographic structure of ternary composite is confirmed using x-ray diffraction and has a significant effect on ionic conductivity. The thermogravimetric analysis result shows a 22.26 wt% loss in the region of 25°C to 900°C due to the evaporation of volatile constituents, including nitrates, carbonates, and moisture. Surface analysis results revealed compact morphology and low porosity with arbitrary grain sizes. Electrochemical impedance spectroscopy has been used to evaluate ionic conductivities. The Mn-ternary composite sintered at 900°C has shown ionic conductivity of 1.63 × 10−6 S/cm at ambient temperature. 8 wt%-LiBr enhanced the ionic conductivity up to 1.68 × 10−4 S/cm by significantly reducing the grain boundaries without high-temperature sintering. Results suggested the suitability of LiBr mixed ternary composites as a favorite candidate for lithium batteries in terms of safety, stability, and high ionic conductivity. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting for sustainable hydrogen and oxygen production have shown enormous potentials. However, this method needs low‐cost and highly active catalysts. Traditional nano catalysts, while effective, have limits since their active sites are mostly restricted to the surface and edges, leaving interior surfaces unexposed in redox reactions. Single atom catalysts (SACs), which take advantage of high atom utilization and quantum size effects, have recently become appealing electrocatalysts. Strong interaction between active sites and support in SACs have considerably improved the catalytic efficiency and long‐term stability, outperforming their nano‐counterparts. This review's first section examines the Hydrogen Evolution Reaction (HER) and the Oxygen Evolution Reaction (OER). In the next section, SACs are categorized as noble metal, non‐noble metal, and bimetallic synergistic SACs. In addition, this review emphasizes developing methodologies for effective SAC design, such as mass loading optimization, electrical structure modulation, and the critical role of support materials. Finally, Carbon‐based materials and metal oxides are being explored as possible supports for SACs. Importantly, for the first time, this review opens a discussion on waste‐derived supports for single atom catalysts used in electrochemical reactions, providing a cost‐effective dimension to this vibrant research field. The well‐known design techniques discussed here may help in development of electrocatalysts for effective water splitting. [ABSTRACT FROM AUTHOR]

The majority of methanol oxidation electrocatalysts are based on platinum‐group metals such as platinum, palladium, and ruthenium. However, their usage is restricted because of their high cost, scarcity, and carbon monoxide toxicity concerns. We devised a simple approach for preparing a nickel foam (NF) based electrode using in‐situ synthesis of metal organic framework, such as Co‐MOF/NF, Ni‐MOF/NF, Mo‐MOF/NF, NC‐MOF/NF, MC‐MOF/NF, NM‐MOF/NF, and NMC‐MOF/NF, as an efficient electrocatalyst for methanol oxidation to produce carbon dioxide and water. Catalysts were synthesized using a hydrothermal process. In methanol with alkaline electrolyte, the as‐prepared NMC‐MOF/NF catalysts had the highest current density response, such as 5641 mA/cm2, in contrast to other bimetallic and single metal‐based metal organic framework electrocatalysts supported on Ni foam. We also observed that the NMC‐MOF/NF could efficiently catalyze the oxidation of carbon monoxide while being relatively unaffected by it. After 20,000 seconds in methanol oxidation, NMC‐MOF/NF based electrode retained about 100 % of its initial activity. Following simple synthesis technique and the improved catalytic efficiency and stability of NMC‐MOF/NF, methanol can be used to generate energy‐efficient products such as hydrogen. [ABSTRACT FROM AUTHOR]

Nanomaterials find several applications in the oilfield operations. In oilwell drilling, nanomaterials are being used for mitigating wellbore instability conditions, improving thermal stability of the fluid, minimizing formation damage by preventing fluid invasion into the reservoir, improving fluid rheology, and controlling fluid loss. A wide range of nanomaterials from organic as well as inorganic and composites are being developed to accomplish the mentioned functions. Significant nanomaterials being developed include nanocellulosic particles, nanoclay, nanosilica, nanometals, nanometal oxides and nanopolymers. Improving fluid properties to develop smart fluids by the incorporation of nanomaterials is an emerging research field which is yielding promising results. This review article presents the recent development made in the applications of the nanomaterials in drilling fluids especially the nanosilica particles surface modified by organic ligands. Surface modification of nanosilica with organic ligands namely 3‐Glycidoxypropyl‐triethoxy silane (GPTS), hyperbranched polyethyleneimine (HPEI) and Moringa oleifera cationic protein (MOCP) are discussed. Applications of nanomaterials in drilling fluids to minimize wellbore instability, prevent formation damage, improve thermal stability and conductivity, stabilize fluid rheology, improve hole cleaning, and minimize the chances of downhole string sticking have been reviewed. [ABSTRACT FROM AUTHOR]

The continuous carbon dioxide (CO2) gas emissions associated with fossil fuel production, valorization, and utilization are serious challenges to the global environment. Therefore, several developments of CO2 capture, separation, transportation, storage, and valorization have been explored. Consequently, we documented a comprehensive review of the most advanced strategies adopted in metal‐organic frameworks (MOFs) for CO2 capture and separation. The enhancements in CO2 capture and separation are generally achieved due to the chemistry of MOFs by controlling pore window, pore size, open‐metal sites, acidity, chemical doping, post or pre‐synthetic modifications. The chemistry of defects engineering, breathing in MOFs, functionalization in MOFs, hydrophobicity, and topology are the salient advanced strategies, recently reported in MOFs for CO2 capture and separation. Therefore, this review summarizes MOF materials′ advancement explaining different strategies and their role in the CO2 mitigations. The study also provided useful insights into key areas for further investigations. [ABSTRACT FROM AUTHOR]

An alternative to fossil fuel is essential to overcome energy shortages and resolve the environmental problem. Hydrogen production via earth‐abundant water resources is a clean, sustainable, and energy‐rich fuel source. For the water splitting process, the catalyst is an essential need to enhance the kinetics of the overall reaction. Therefore, noble metals are used as the state‐of‐the‐art catalyst for the OER and HER process due to their remarkable efficiency and stability. But, their high cost and inadequacy are the main obstructs to their commercialization. To commercialize the process, researchers are trying to replace the expensive noble catalyst with a non‐noble stable, conductive, and more productive catalyst. In recent decades, transition metal based metal organic framework (MOF) has been extensively used as an electro‐catalyst to enhance the kinetics of the OER and HER process. MOF as an electro‐catalyst is a promising candidate to improve the rate of water splitting reaction due to their inherent properties such as high surface area, tunable morphology, and high porosity. In this review, the significant data of recent years are assembled for the water splitting process by using the MOFs as an electro‐catalyst. This review not only captures the advancement in MOF materials with the effective approach of designing but also indicates the catalyst evaluation parameters and detailed mechanism of the HER and the OER process. Meanwhile, challenges and future prospectus of the MOF based catalyst for the water splitting process are also described here. Hopefully, this review article will help to develop a more productive MOF for the generation of green and sustainable hydrogen. [ABSTRACT FROM AUTHOR]

In the past few years, biofuels have emerged as renewable alternative to encounter global energy requirements in a greener way. Biomass is a sustainable cost‐effective natural resource with wide diversity for conversion to biofuel such as biodiesel, biogas, bio‐oil, biohydrogen, etc. via various chemical, thermal, or biochemical routes. Catalysis plays a pivotal role to convert biomass to biofuels, but conventional catalysts show a lot of short comings. To address these problems, a novel nanocatalysts approach is considered to be the most promising option. Nanocatalysts offer extremely high surface area, enhanced selectivity, better stability and catalytic activity at an atomic and molecular level in comparison to bulk catalysis. Here an insight about the limitation of traditional catalysts, the importance of nanocatalysts, various types of nanocatalysts, and their application in conversion of biomass to biofuel is given. It emphasizes the state‐of‐the‐art developments in terms of catalysis and catalytic processes that are anticipated to play a crucial role in biomass conversion to fuel are emphasized and the chemistry behind nanocatalyst design for biofuel production and reduction of inhibitory effect is highlighted. [ABSTRACT FROM AUTHOR]

A considerable concern in exploring clean, efficient, and renewable energy resources to effectively replace fossil fuels and to combat the environmental problems and energy scarcities for a sustainable future has been observed. In this context, hydrogen is a clean, renewable, energetically efficient fuel with infinite potential for the future, which can generate a large amount of energy through the electrocatalytic splitting of earth‐abundant water resources. Noble metals, owing to their extraordinary efficiency and stability, are state‐of‐the‐art catalysts for the oxygen evolution reaction (OER) process. However, their scarcity and high cost hamper their commercialization. To replace these expensive noble‐metal‐based materials, researchers are extensively working on the development of cost effective, stable, conductive, and efficient non‐noble metal based materials such as transition metal oxides, borides, nitrides, sulfides, phosphides, selenides, perovskites oxides, and layered double hydroxides, where the incorporation of heteroatoms improves the electrocatalytic activity by modifying the electronic structure and enhances the conductivity and stability. In the case of transition‐metal based metal organic frameworks (MOFs) and MOF‐derived materials, the unique structure of MOFs with a high surface area and porosity, as well as rich redox chemistry of transition metals, leads to excellent response towards the OER process. Moreover, direct utilization of carbonaceous materials or making their composites with transition metals not only enhances the conductivity due to their conductive nature but also promotes stability by strongly binding with the electrocatalyst. Owing to the presence of functional groups on the surface or through different interactions, they provide multiple paths for facile electron and ion transport due to the sheet/network like structure, which help in the fine dispersion of electrocatalyst due to high surface area, prevent agglomeration, and in turn results in improved electrocatalytic activity. Besides these advances, a) there is still a need for a thorough understanding of reaction mechanism via in situ spectroscopic techniques to further optimize the composition and design of electrocatalyst to get desired results, b) the stability of the materials should be further enhanced to practically utilize synthesized material under harsh conditions without degradation, and c) the utilization of these optimized OER catalysts in a solar cell to consume solar energy (renewable energy source), remains a key requirement of the modern era. [ABSTRACT FROM AUTHOR]

In this research, electrocatalytic activity of cobalt benzene tricarboxylic acid metal organic framework (Co BTC MOF) and its reduced graphene oxide based composites (rGO/Co BTC) were investigated in an alkaline media for the methanol oxidation reaction (MOR). Metal Organic frameworks (MOF) and their composites were solvothermally prepared and characterized via FTIR, EDX, SEM and XRD. Electrochemical studies were performed by cyclic voltammetry, electron impedance spectroscopy, chronoamperometry and cyclic stability. Among all the prepared composites, 1 wt % rGO/Co BTC MOF (1.07 mg cm−2) demonstrated a promising current density of 130 mA cm−2 at 1.59 V vs. RHE, a tafel slope of 83.6 mV dec−1 and resistance of 14.75 Ω in 1 M NaOH/ 2 M methanol solution showing much better performance than state‐of‐the‐art Pt based materials. [ABSTRACT FROM AUTHOR]

Cover Feature: Recent Advances in Electrocatalysis of Oxygen Evolution Reaction using Noble-Metal, Transition-Metal, and Carbon-Based Materials (ChemElectroChem 3/2021) Keywords: Electrocatalysts; Hydrogen production; Oxygen Evolution Reaction (OER); Activity parameters; Metal Organic Frameworks (MOFs) EN Electrocatalysts Hydrogen production Oxygen Evolution Reaction (OER) Activity parameters Metal Organic Frameworks (MOFs) 427 427 1 02/13/21 20210201 NES 210201 B The Cover Feature b illustrates noble-metal, transition-metal, and carbon-based compounds effectively utilized for oxygen evolution reaction electrocatalysis. Electrocatalysts, Hydrogen production, Oxygen Evolution Reaction (OER), Activity parameters, Metal Organic Frameworks (MOFs). [Extracted from the article]