Effective oxygen reduction/evolution nanoporous cobalt–nitrogen–carbon based catalysts are developed from rationally designed single-precursor CoxZn100−x–ZIF-8 with controlled graphitization.

Metal sulfides are commonly used in energy storage and electrocatalysts due to their redox centers and active sites. Most literature reports show that their performance decreases significantly caused by oxidation in alkaline electrolyte during electrochemical testing. Herein, S and N co‐doped graphene‐based nickel cobalt sulfide aerogels are synthesized for use as rechargeable alkaline battery electrodes and oxygen reduction reaction (ORR) catalysts. Notably, this system shows improved cyclability due to the stabilization effect of the S and N co‐doped graphene aerogel (SNGA). This reduces the rate of oxidation and the decay of electronic conductivity of the metal sulfides materials in alkaline electrolyte, i.e., the capacity decrease of CoNi2S4/SNGA is 4.2% for 10 000 cycles in a three‐electrode test; the current retention of 88.6% for Co—S/SNGA after 12 000 s current–time chronoamperometric response in the ORR test is higher than corresponding Co—S nanoparticles and Co—S/non‐doped graphene aerogels. Importantly, the results here confirm that the Ni—Co—S ternary materials behave as an electrode for rechargeable alkaline batteries rather than supercapacitors electrodes in three‐electrode test as commonly described and accepted in the literature. Furthermore, formulas to evaluate the performance of hybrid battery devices are specified.

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We report the synthesis, structure, and characterization of two novel porous zeolite-like supramolecular assemblies, ZSA-1 and ZSA-2, having zeolite gis and rho topologies, respectively. The two compounds were assembled from functional metal-organic squares (MOSs) via directional hydrogen-bonding interactions and exhibited permanent microporosity and thermal stability up to 300 °C.

Electrocatalysis of ethylene glycol oxidation (EGO) on shape-controlled Pd nanocrystals is of great interest in the pursuit of efficient biomass fuel utilization and nanomaterial application. The present work is aimed at a mechanistic study of electrocatalytic EGO in alkaline media on surface-cleaned high-index Pd concave nanocubes (Pd CNCs) with and without surface Bi modification. CO-adsorption displacement effectively removes the surfactants on as-synthesized Pd CNCs, facilitating controlled Bi adatom formation. EGO on the Pd CNCs is notably enhanced as a result of Bi modification, with the activity peak at a Bi coverage of ca. 0.31 in terms of apparent and specific oxidation current densities. Internal (ATR-SEIRAS) and external (IRRAS) reflection modes of in situ infrared spectroscopy have been used to probe the EGO process at a molecular level. High surface sensitivity ATR-SEIRAS enabled ready identification of the formation and removal of CO and 2-hydroxyacetyl surface species during EGO on Pd CNCs and Bi-modified Pd (Bi/Pd) CNCs. In comparison to that on bare Pd CNCs, the CO ad band is significantly stronger on Bi/Pd CNCs, suggestive of a promoted C−C bond cleavage. IRRAS results further reveal that glycolate and glyoxal are the main products of EGO on both pristine and Bi/Pd CNCs. In addition, formations of glyoxal, CO, and CO 2 on Bi/Pd CNCs are relatively enhanced, in comparison to those on bare Pd CNCs. On the basis of the comprehensive spectral results and literature reports, relevant reaction pathways are proposed for EGO at Pd and Bi/Pd CNCs in alkaline media.

Two novel MMOFs, JLU-Liu5 and JLU-Liu6, are based on ternary building units and exhibit high adsorption selectivity for CO2, C2H6 and C3H8 over CH4, which is attributed to steric effects and host-guest interactions. These MMOFs are promising materials for gas adsorption and natural gas purification.

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Aqueous solutions of polyoxometalates (POMs) have been shown to have potential as high-capacity energy storage materials due to their potential for multi-electron redox processes, yet the mechanism of reduction and practical limits are currently unknown. Herein, we explore the mechanism of multi-electron redox processes that allow the highly reduced POM clusters of the form {MO 3 } y to absorb y electrons in aqueous solution, focusing mechanistically on the Wells–Dawson structure X 6 [P 2 W 18 O 62 ], which comprises 18 metal centers and can uptake up to 18 electrons reversibly ( y = 18) per cluster in aqueous solution when the countercations are lithium . This unconventional redox activity is rationalized by density functional theory, molecular dynamics simulations, UV–vis, electron paramagnetic resonance spectroscopy, and small-angle X-ray scattering spectra. These data point to a new phenomenon showing that cluster protonation and aggregation allow the formation of highly electron-rich meta-stable systems in aqueous solution, which produce H 2 when the solution is diluted. Finally, we show that this understanding is transferrable to other salts of [P 5 W 30 O 110 ] 15– and [P 8 W 48 O 184 ] 40– anions, which can be charged to 23 and 27 electrons per cluster, respectively.