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Hydrogen, especially the green hydrogen based on water electrolysis, is of great importance to build a sustainable society due to its high-energy-density, zero-carbon-emission features, and wide-range applications. Today's water electrolysis is usually carried out in either low-temperature (700 degrees C) applications, e.g., solid oxide electrolyzer. However, the low-temperature devices usually suffer from high applied voltages (usually >1.5 V @0.01 A cm(-2)) and high cost; meanwhile, the high-temperature ones have an unsatisfied lifetime partially due to the incompatibility among components. Reasonably, an intermediate-temperature device, namely, proton ceramic cell (PCC), has been recently proposed. The widely-used air electrode for PCC is based on double O2-/e(-) conductor or composited O2-/e(-) -H+ conductor, limiting the accessible reaction region. Herein, we designed a single-phase La0.8Sr0.2Co1-xMnxO3-delta (LSCM) with triple H+/O2-/e(-) conductivity as the air electrode for PCCs. Specifically, the La0.8Sr0.2Co0.8Mn0.2O3-delta (LSCM8282) incorporates 5.8% proton carriers in molar fraction at 400 degrees C, indicating superior proton conducting ability. Impressively, a high current density of 1580 mA cm(-2) for hydrogen production (water electrolysis) is achieved at 1.3 V and 650 degrees C, surpassing most low- and high-temperature devices reported so far. Meanwhile, such a PCC can also be operated under a reversible fuel cell mode, with a peak power density of 521 mW cm(-2) at 650 degrees C. By correlating the electrochemical performances with the hydrated proton concentration of single-phase triple conducting air electrodes in this work and our previous work, a principle for rational design of high-performance PCCs is proposed. (C) 2022 The Chinese Ceramic Society. Production and hosting by Elsevier B.V.

The leaching and non-recoverability of mental ions have always limited the practical application of Fenton-like processes. For the first time, we synthesized molybdenum phosphide (MoP) with dual active sites for the degradation of diclofenac (DCF) in the Fenton-like process. The DCF degradation rate constant (k) of MoP + H2O2 process was calculated to be 0.13 min-1 within 40 min, indicating a highly efficient catalytic ability of MoP. In addition, this catalyst exhibits a stable structure and good activity, which could apply in a broad pH range, different ions solution and real wastewater condition. Accordingly, this efficient catalytic capability may be attributed to the presence of the metal sites Moδ+ and the electron-rich sites Pδ− in MoP, which could induce the generation of hydroxyl radical (•OH) and superoxide radical (•O2−) through electron transfer, resulting in the effective removal of DCF. This study provides an idea for the optimization of Fenton-like technologies and environmental remediation.

The waxberry-like mixed-phase TiO2 hollow microstructures (WMTHMs) are controllably prepared via a topotactic synthetic method, involving the synthesis of monodispersed CaTiO3 precursors by a solvothermal method and subsequently transforming them into TiO2 through a Na2EDTA-assisted ion-exchange process. The ratio of anatase-rutile is adjustable, and the two phases are connected well with each other. WMTHMs are composed of radially aligned nanorods, speeding up the electron transport. The optimum WMTHMs sample shows a specific surface area of 68.05 m2/g and exhibits an excellent light scattering capacity. The cell based on WMTHMs light scattering layer obtained an optimal efficiency of 9.12%. The improvement of cell efficiency is mainly attributed to the high specific surface area, the efficient light scattering, the appropriate ratio of anatase-rutile, the staggered bandgap structure, and the convenient one-dimensional electron transport channel.

Controllable doping of a Pt single-atom into the octahedral sites of a spinel Mn3O4 lattice leads to a moderate rise of the d-band-center, which guarantees the adsorption of key intermediates for superior hydrogen evolution reaction.

An efficient method to construct isoindolo[2,1-b]isoquinolin-5(7H)-ones via a Rh(iii)-catalyzed direct C–H oxidative annulation of isoquinolones with allyl alcohols has been developed.

Oxygen catalytic reaction was promoted by the enhanced utilization rate of highly active Co3+ after the reconstruction of Co3O4.

A significant enhancement effect of electron traps on the optical thermometry performance in ZnGa2O4:Mn is demonstrated by experimental and calculation results.

2D/2D BiVO4 nanosheet/rGO nanocomposites were found to be highly active for direct nitrate synthesis by photocatalytic nitrogen fixation.

Electrochemical overall water splitting is attracting a broad focus as a promising strategy for converting the electrical output of renewable resources into chemical fuels, specifically oxygen and hydrogen. However, the urgent challenge in water electrolysis is to search for low-cost, high-efficiency catalysts based on earth-abundant elements as an alternative to the high-cost but effective noble metal-based catalysts. The transition metal-based catalysts are more appealing than the noble metal catalysts because of its low cost, high performance and long stability. Some recent advances for the development in overall water splitting are reviewed in terms of transition metal-based oxides, carbides, phosphides, sulfides, and hybrids of their mixtures as hybrid bifunctional electrocatalysts. Concentrating on different catalytic mechanisms, recent advances in their structural design, controllable synthesis, mechanistic insight, and performance-enhancing strategies are proposed. The challenges and prospects for the future development of transition metal-based bifunctional electrocatalysts are also addressed.

A one-pot three-component synthesis of multifunctionalized isoquinolones from 2-oxazolines, iodonium ylides, and carboxylic acids via Rh(III)-catalyzed oxazolinyl-directed C-H activation and tandem annulation under redox-neutral conditions has been developed. This catalytic system is characterized by readily available starting materials, a wide tolerance of functional groups, a short reaction time, and high yields. The synthetic utility of the cascade reaction was further demonstrated by a gram-scale synthesis and derivatization of the obtained products.

Drop-casting manganese oxide (MnO

Heterostructured catalysts show outstanding performance in electrochemical reactions owing to their beneficial interfacial properties. However, the rational design of heterostructured catalysts with the desired interfacial properties and charge-transfer characteristics is challenging. Herein, we developed a SrMn3 O6-x -SrMnO3 (SMOx -SMO) heterostructure through epitaxial growth, which demonstrated excellent electrocatalyst performance for the oxygen reduction reaction (ORR). The formation of high-valence Mn3+/4+ is beneficial for promoting a positive shift in the position of the d-band center, thereby optimizing the adsorption and desorption of ORR intermediates on the heterojunction surface and resulting in improved catalytic activity. When SMOx -SMO was applied as an air-electrode catalyst in a rechargeable zinc-air battery, a high output voltage and power density was achieved, with performance comparable to a battery prepared with Pt/C-IrO2 air-electrode catalysts, albeit with much better cycling stability.

The synthesis of C3-substituted isoindolin-1-ones from oxazolines and cyclopropanols has been achieved with oxazoline as a bifunctional nucleophilic directing group. The reaction proceeds by the cleavage of three chemical bonds and allows the formation of three new chemical bonds, a C-N bond, a C-C bond, and a C-O bond, in a single step.

Layered double hydroxides (LDHs) with decent oxygen evolution reaction (OER) activity have been extensively studied in the fields of energy storage and conversion. However, their poor conductivity, ease of agglomeration, and low intrinsic activity limit their practical application. To date, improvement of the intrinsic activity and stability of NiFe-LDHs through the introduction of heteroatoms or its combination with other conductive substrates to enhance their water-splitting performance has drawn increasing attention. In this study, vertically interlaced ternary phosphatised nickel/iron hybrids grown on the surface of titanium carbide flakes (NiFeP/MXene) were successfully synthesised through a hydrothermal reaction and phosphating calcination process. The optimised NiFeP/MXene exhibited a low overpotential of 286 mV at 10 mA cm−2 and a Tafel slope of 35 mV dec−1 for the OER, which exceeded the performance of several existing NiFe-based catalysts. NiFeP/MXene was further used as a water-splitting anode in an alkaline electrolyte, exhibiting a cell voltage of only 1.61 V to achieve a current density of 10 mA cm−2. Density functional theory (DFT) calculations revealed that the combination of MXene acting as a conductive substrate and the phosphating process can effectively tune the electronic structure and density of the electrocatalyst surface to promote the energy level of the d-band centre, resulting in an enhanced OER performance. This study provides a valuable guideline for designing high-performance MXene-supported NiFe-based OER catalysts.

Photoelectrocatalytic (PEC) CO

Despite the fact that high-valent nickel-based oxides exhibit promising catalytic activity for the urea oxidation reaction (UOR), the fundamental questions concerning the origin of the high performance and the structure-activity correlations remain to be elucidated. Here, we unveil the underlying enhanced mechanism of UOR by employing a series of prepared cation-vacancy controllable LiNiO

The catalytic conversion of alcohols under mild conditions is a great challenge because it is constrained by low selectivity and low activity. Herein, we demonstrate a hollow nanotube Fe2 O3 /MoO3 heterojunction (FeMo-2) for the photoelectrocatalytic conversion of small-molecule alcohols. Experimental and theoretical analyses reveal that the optical carrier transfer rate is enhanced by constructing interfacial internal electric fields and Fe-O-Mo charge transfer channels. For the formox process, heterojunctions possess superior HCHO-selective reaction paths and free energy transitions, optimizing the selectivity of HCHO and enhancing the reactivity. FeMo-2 shows a greatly improved performance compared to single Fe2 O3 ; the photocurrent density of FeMo-2 reaches 0.66 mA cm-2 , which is 3.88 times that of Fe2 O3 (0.17 mA cm-2 ), and the Faraday efficiency of the CH3 OH-to-HCHO conversion is 95.7 %. This work may deepen our understanding of interfacial charge separation and has potential for the production of HCHO and for conversion reactions of other small-molecule alcohols at cryogenic temperatures.

Herein, we report a one-step synthesis of a hollow Fe-N/C catalyst via a hard-templating strategy, in which FeNx sites are well dispersed on the carbon sphere. In particular, we found an optimal iron ratio on the catalyst surface for an enhanced alkaline oxygen reduction reaction (ORR). The catalyst with a high specific surface area of 311.71 m2 g-1 exposes abundant electroactive sites that facilitate the adsorption of oxygen intermediates, thus exhibiting superior ORR activity in alkaline solution.