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In pursuing green hydrogen fuel, electrochemical water-splitting emerges as the optimal method. A critical challenge in advancing this process is identifying a cost-effective electrocatalyst for oxygen evolution on the anode. Recent research has demonstrated the efficacy of first-row transition metal carbonates as catalysts for various oxidation reactions. In this study, Earth-abundant first-row transition metal carbonates were electrodeposited onto nickel foam (NF) electrodes and evaluated for their performance in the oxygen evolution reaction. The investigation compares the activity of these carbonates on NF electrodes against bare NF electrodes. Notably, Fe2(CO3)3/NF exhibited superior oxygen evolution activity, characterized by low overpotential values, i.e. Iron is master of them all (R. Kipling, Cold Iron, Rewards and Fairies, Macmillan and Co. Ltd., 1910). Comprehensive catalytic stability and durability tests also indicate that these transition metal carbonates maintain stable activity, positioning them as durable and efficient electrocatalysts for the oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Lithium sulfide (Li2S) is the critical raw material used for the synthesis of sulfide solid-state electrolytes, but its high cost and pollution restrict the commercialization of sulfide solid-state electrolytes and sulfide-based all-solid-state batteries. A new green and cost-effective method for the synthesis of high-quality Li2S is designed and proposed in this work. The method of reducing Li2SO4 with H2 circumvents the disadvantages of many side reactions, complicated purification processes, impure products and emission of greenhouse gases (CO and CO2) associated with traditional carbothermal reduction methods, and high-purity Li2S (H-Li2S) is obtained. Subsequently, H-Li5.6PS4.6Cl1.4 solid electrolyte was synthesized and compared with the C-Li5.6PS4.6Cl1.4 electrolyte synthesized from commercial Li2S (C-Li2S). The ionic conductivity (8.06 mS cm−1) and chemical/electrochemical stability as cathode/anode material were better than those of C-Li5.6PS4.6Cl1.4. Besides, the rate performance and long cycling stability of an all-solid-state lithium battery NCM//Li5.6PS4.6Cl1.4//Li–In assembled with H-Li5.6PS4.6Cl1.4 are better than those of batteries assembled with C-Li5.6PS4.6Cl1.4. It can maintain a discharge capacity of 133.23 mA h g−1 after 300 cycles at 1C (95% of the initial discharge capacity), and has a high discharge capacity of 127.9 mA h g−1 at 3C. The high electrochemical performance of the all-solid-state battery confirms the superiority of high-purity H-Li2S and the advantages of the hydrogen reduction method. [ABSTRACT FROM AUTHOR]

Lignin, a crucial component of lignocellulosic biomass, holds immense promise for advancing biorefineries and producing sustainable energy alternatives. This study engineered a CN/rGO/BMO (2 : 1) heterojunction photocatalyst with varying Pd NP loading to selectively target the hydrogenolysis of challenging C–O ether bonds in lignin model compounds. Specific focus was on β-O-4, α-O-4, and the formidable 4-O-5 linkages. The 4-O-5 linkage, due to its high dissociation energy, poses a significant challenge. Electrochemical and spectral analyses unveiled improvements in charge separation, leading to delayed recombination of charge carriers in the heterojunction photocatalyst. Decorating the heterojunction with Pd NPs exhibited an elevated work function and a low Fermi energy level, facilitating the accommodation of photogenerated electrons and enabling efficient H2 dissociation. Such enhancement facilitated the cleavage of all three linkages, including the resistant 4-O-5 bonds under ambient conditions. The photocatalyst exhibited effective cleavage, yielding aromatic (toluene, phenol, ethylbenzene) and aliphatic (cyclohexane, ethylcyclohexane) products. Selectivity modulation was achieved by adjusting the time, hydrogen pressure, and Pd loading. Furthermore, this photocatalytic approach successfully transformed simulated lignin bio-oil containing all three linkages into valuable monomers. The alcoholic solvents efficiently harnessed photogenerated holes and prevented electron–hole recombination. The photocatalyst also demonstrated the capability to produce monomers from the native lignin extracted from teak wood sawdust. Emphasizing the focus on the reaction pathway and mechanism, scavenging studies and analyses were conducted, including UPS and VBXPS, to establish the Z-scheme charge transfer mechanism within the heterojunction. These findings provide a sustainable and efficient pathway for lignin valorisation in biorefineries, significantly contributing to the advancement of green fuels and aligning with the principles of green chemistry. [ABSTRACT FROM AUTHOR]

A new catalytic transfer hydrogenation (CTH) strategy was developed for the continuous conversion of furfural (FF) into furfuryl alcohol (FFA) with Cu/ZnO/Al2O3 (CZA) as the catalyst under mild conditions. Methanediol was used as the hydrogen donor without any hazardous gas emission. FF was converted into FFA with up to 99% selectivity at 108 °C and normal pressure under an N2 atmosphere. The highly dispersive copper species (Cu0, Cu+) with few Lewis acidic sites and η1(O)-type adsorption ensured high selectivity and mild conversion. Deuterium-labelling experiments revealed that, in the presence of formaldehyde, water is split into hydrogen species, which can reduce FF to form FFA. A reasonable reaction mechanism for the conversion of FF into FFA via transfer hydrogenation was proposed. Notably, this strategy offers a new route to splitting water to generate in situ "green hydrogen" for the hydrogenation of unsaturated organic compounds under mild conditions based on non-noble heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Electro-catalytic water splitting is widely viewed as an efficient and viable strategy for green hydrogen production. Herein, we designed nanostructured nickel–cobalt alloy grown on the reduced graphene oxide-single walled carbon nanotube (rGO-SWCNT) thin film by means of electro-deposition, which was used to catalyze water splitting for hydrogen evolution reaction (HER) in an alkaline medium. It was found that the HER performance of nickel–cobalt alloys was determined by the Co/Ni ratio and better than their corresponding single components Co and Ni. Nickel–cobalt alloy with a Co/Ni ratio of 2 (CoNi21) exhibited the most notable HER efficiency with an overpotential of 83.5 mV and 291.8 mV vs. reversible hydrogen electrode at 10 mA cm−2 and 100 mA cm−2, respectively. Furthermore, the significantly lower Tafel slope (112.6 mV dec−1) of CoNi21 indicates that the HER kinetics of the nickel–cobalt alloy is accelerated due to the synergistic effect of Ni and Co. The charge-transfer resistance of CoNi21 is significantly low compared to any single component, validating the intensified interfacial charge transfer. Besides, CoNi21 has the highest active surface area of 147.1 mF cm−2 on the basis of the ECSA measurements, which can be beneficial for providing rich active sites. The CoNi21 catalyst offered excellent durability for HER in the alkaline medium. This work provides a combinatorial method integrating rich interfaces of Co–Ni alloy on highly conductive carbon substrate to design efficient and low-cost electrocatalysts for improving the HER performance. [ABSTRACT FROM AUTHOR]

This study presents a pioneering nanohybrid catalyst featuring hierarchically porous dual-functional (acid–base) active sites, which is a versatile catalyst for the crucial bio-glycerol acetalization reaction. The nanohybrid catalyst demonstrated remarkable efficiency in converting bio-diesel derived waste glycerol into excellent green fuel additive 'solketal,' achieving an unprecedented yield of approximately 99%. Insights into the structural properties and the relationship between the structure and properties of the catalyst were obtained through various characterization techniques, including FTIR spectroscopy, XRD, NH3-TPD, CO2-TPD, 27Al-NMR spectroscopy, SEM, TEM, UV-Vis spectroscopy, and X-ray photoelectron spectroscopy. The hybrid catalyst shows several highly desirable properties, including enhanced acidity, a strong affinity for reactants, mesoporosity, stability, and the proximity of potent acidic and basic sites. Simplicity, cost-effectiveness, exceptional recyclability, and resistance to moisture make the synthesized MgAl-oxide/HZSM-5 (MAZ) nanohybrid catalyst an appealing candidate for potential commercial applications in bio-refinery processes. [ABSTRACT FROM AUTHOR]

Seawater electrolysis provides a desirable pathway for large-scale production of green hydrogen without dependence on freshwater. However, its practical application is seriously hindered by low energy efficiency and insufficient durability because of the detrimental chlorine electro-oxidation and complex components of seawater. Herein, 2D MoN/Co2N hybrid nanosheets grown on 1D Cu nanowires and integrated on 3D Cu foam electrodes (Co/Mo–N–C/Cu) were fabricated for seawater splitting, which could enable the alkaline seawater electrolyzer assembled with these hierarchically structural electrodes to achieve a current density of 100 mA cm−2 at a low voltage of 1.70 V, along with good stability due to the synergistic effect among the MoN/Co2N hybrid nanosheets, unique 1D/2D/3D hierarchical structure, and the N-doped carbon protection layer. Theoretical calculations demonstrated that strong electron transfer occurred at heterogeneous interfaces, which could mediate the adsorption and desorption of intermediates, thus reducing the reaction energy barriers. [ABSTRACT FROM AUTHOR]

Formic acid is used as a green carrier for hydrogen storage and production. Here, in order to achieve rapid dehydrogenation of formic acid, the catalyst PdNi/OPDA-MWCNTs is synthesized by reducing bimetallic PdNi nanoparticles on o-phenylenediamine (OPDA) modified multi-walled carbon nanotubes (MWCNTs). Ultrafine metal nanoparticles with a size of 2.6 nm are obtained in the presence of amine groups. The catalyst system Pd0.7Ni0.3/OPDA-MWCNTs catalyzes hydrogen production from formic acid in an additive-free environment with excellent activity, reaching the turnover frequency (TOF) value of 1303 h−1 at 323 K. This is comparable to most reported values. In addition, the catalyst maintains good catalytic activity in five-cycle tests under the same conditions. [ABSTRACT FROM AUTHOR]

This document contains profiles of researchers in the field of chemistry who have made significant contributions to their respective fields. The profiles provide information about their educational background, research interests, and notable achievements. The researchers come from diverse backgrounds and work on various topics, such as organic synthesis, bio-inspired coatings, nanomaterials, and electrocatalysis. These profiles offer valuable insights into the work being done by these researchers and may be useful for library patrons conducting research in these areas. [Extracted from the article]

Water is known for dissipating electrostatic charges, but it is also a universal agent of matter electrification, creating charged domains in any material contacting or containing it. This new role of water was discovered during the current century. It is proven in a fast-growing number of publications reporting direct experimental measurements of excess charge and electric potential. It is indirectly verified by its success in explaining surprising phenomena in chemical synthesis, electric power generation, metastability, and phase transition kinetics. Additionally, electrification by water is opening the way for developing green technologies that are fully compatible with the environment and have great potential to contribute to sustainability. Electrification by water shows that polyphasic matter is a charge mosaic, converging with the Maxwell–Wagner–Sillars effect, which was discovered one century ago but is still often ignored. Electrified sites in a real system are niches showing various local electrochemical potentials for the charged species. Thus, the electrified mosaics display variable chemical reactivity and mass transfer patterns. Water contributes to interfacial electrification from its singular structural, electric, mixing, adsorption, and absorption properties. A long list of previously unexpected consequences of interfacial electrification includes: "on-water" reactions of chemicals dispersed in water that defy current chemical wisdom; reactions in electrified water microdroplets that do not occur in bulk water, transforming the droplets in microreactors; and lowered surface tension of water, modifying wetting, spreading, adhesion, cohesion, and other properties of matter. Asymmetric capacitors charged by moisture and water are now promising alternative equipment for simultaneously producing electric power and green hydrogen, requiring only ambient thermal energy. Changing surface tension by interfacial electrification also modifies phase-change kinetics, eliminating metastability that is the root of catastrophic electric discharges and destructive explosions. It also changes crystal habits, producing needles and dendrites that shorten battery life. These recent findings derive from a single factor, water's ability to electrify matter, touching on the most relevant aspects of chemistry. They create tremendous scientific opportunities to understand the matter better, and a new chemistry based on electrified interfaces is now emerging. [ABSTRACT FROM AUTHOR]

The development of photocatalysts plays a pivotal role in facilitating the production of green hydrogen energy through water splitting. In this study, one-dimensional (1D) organic–inorganic ZnCdS(EDA)/Ni@NiO (EDA: ethylenediamine) nanorods were prepared by combining organic molecules of EDA into ZnCdS. The EDA molecule possesses two amino functional groups with strong electron-donating capacity, thereby facilitating electron transfer to ZnCdS(EDA)/Ni@NiO and enabling efficient hydrogen evolution through photocatalytic water splitting. The H2 evolution rate of ZnCdS(EDA)/Ni@NiO was 159 μmol g−1 h−1 in the absence of sacrificial agents, and its H2 evolution rate in the system with EDA as the sacrificial agent can reach 5760 μmol g−1 h−1. The combination of EDA, a S vacancy, and heterojunction was proved to be the main factor for improving the separation and transfer rate of photogenerated carriers. The incorporation of ZnCdS(EDA)/Ni@NiO enhances the participation of photogenerated electrons in the photocatalytic hydrogen evolution reaction, thereby improving the overall photocatalytic activity. The synthesis of this one-dimensional composite catalyst holds great potential for advancing the development of efficient photocatalytic materials. [ABSTRACT FROM AUTHOR]

Fast-growing plants with a high carbon fixation capability are promising candidates for mitigating climate change and serving as a renewable resource to replace fossil fuels. Nonetheless, their short lifespan and extensive use lead to the significant accumulation of underutilized waste. While conventional thermal energy extraction remains dominant in biomass utilization, the lack of appropriate carbon capture and storage techniques results in unavoidable CO2 emissions. In contrast, the fine reforming of lignocellulosic biomass offers the potential to reduce CO2 emissions. However, the polymeric, complex and rigid structure of lignocellulosic biomass poses challenges, necessitating energy-intensive pretreatment, where the balance between wood particle size reduction (and thus energy consumption) and pretreatment duration is often overlooked. Herein, we developed a facile energy-saving microwave-hydrothermal method to advance the utilization of fast-growing Paulownia. The optimized sugars (xylose and glucose) after pretreatment can be further converted to formate via a hybrid electrolysis process with the cogeneration of green hydrogen. Both xylose and glucose can be readily converted to formate with high yield and selectivity. This process can be directly powered by PV panel without the safety concerns of hydrogen crossover because oxygen evolution is greatly suppressed. This solar-driven hybrid electrolysis of pretreated Paulownia suggests a pathway to cogenerate green chemicals and green fuels from fast-growing woods while also storing energy from renewable sources in chemical bonds. Overall, this novel synthesis process for green chemicals contributes to the decarbonization efforts and sustainable development initiatives. [ABSTRACT FROM AUTHOR]

To reach a decarbonized future, the conversion of greenhouse gases into green fuels and valuable chemicals is of crucial importance. Methane emissions are the second most significant contributor to global warming. Recent advances in electrocatalytic partial oxidation of methane to high-value fuels at ambient temperatures promise to sidestep the requirement of high temperature in conventional thermal catalysis and provide a revolutionary, sustainable, and decentralized alternative to flaring. Electrocatalysts that can selectively produce valuable compounds from methane under mild conditions are essential for commercialization. This review covers current developments in the electrochemical partial oxidation of methane to oxygenates, with an emphasis on metal oxide electrocatalysts. The regularly deployed strategies, including doping and interface engineering, are systematically reviewed in detail. In addition, the design of the electrolytic cell, the electrolyte, time, potential, and temperature are examined thoroughly and discussed. [ABSTRACT FROM AUTHOR]

The coordination environment and networks of metal–organic frameworks (MOFs) play a significant role in their functional properties, especially catalysis. In recent years, the use of MOFs for electrocatalytic water-splitting reactions to produce green hydrogen fuel has gained increasing attention. Herein, we report the preparation of Co-benzene dicarboxylic acid-based MOFs (Co-MOF-1 and Co-MOF-2) with different coordination environments and correlated their structure-controlled electrocatalytic OER activity in an alkaline medium. Both Co-MOF-1 and Co-MOF-2 showed 3D network structures with different coordination environments around the Co metal centre. In Co-MOF-1, the Co metal centre is coordinated with DMF and pyridine along with a benzene dicarboxylic acid (BDC) ligand, whereas the Co metal centre is coordinated only with BDC ligands in Co-MOF-2. The Co metal centres in Co-MOF-1 contain labile solvent coordination but have completely saturated coordination with the BDC ligand alone in Co-MOF-2. Interestingly, Co-MOF-1 showed relatively strong OER activity and required the overpotential (η) of 294 mV to produce 10 mA cm−2 current density. However, Co-MOF-2 required the overpotential of 343 mV to achieve the 10 mA cm−2 current density. Further Co-MOF-1 showed comparatively low Tafel slope and charge transfer resistance and high electrochemical surface area than Co-MOF-2 and supported the enhanced OER activity. XPS analysis of Co-MOF-1 before and after catalysis suggested the conversion of Co-MOF-1 to CoOOH during the electrocatalysis that boosted the OER activity. The presence of a labile coordination site in Co-MOF-1 might have facilitated the interaction of hydroxyl electrolyte with the metal centre and active site generation by forming CoOOH easily which enhanced the OER activity. Co-MOF-1 also showed excellent stability for over 48 h. Hence, the present work provides structural insight for designing new MOFs for electrocatalytic water-splitting reactions. [ABSTRACT FROM AUTHOR]

Here, we report an efficient catalytic process that operates on a bi-metallic ZSM-5 supported catalyst (0.1Ga–1Zn/ZSM-5) for 100% carbon conversion of glycerol to produce 71.4C% liquid fuel-stock possessing a high concentration of alkyl-aromatics and octane potential (>97 RON) for fuel applications, achieved and reported for the first time to the best of our knowledge. In addition, the H2-rich (36 mol%) gas stream produced as a byproduct is attractive for green fuel applications. The process adds up to an ∼80% increase in the value addition of bio-glycerol, which improves the overall fuel yield of the biodiesel production process towards improved atom efficiency and process economy. [ABSTRACT FROM AUTHOR]