Searching for the highly active, stable, and high-efficiency bifunctional electrocatalysts for overall water splitting, e.g., for both oxygen evolution (OER) and hydrogen evolution (HER), is paramount in terms of bringing future renewable energy systems and energy conversion processes to reality. Herein, three-dimensional (3D) NiFeN nanoparticles/reduced graphene oxide (r-GO) aerogel electrocatalysts were fabricated using precursors of (Ni,Fe)/r-GO alginate hydrogels through an ion-exchange process, followed by a convenient one-step nitrogenization treatment in NH at 700 °C. The resultant materials exhibited excellent electrocatalytic performance for OER and HER in alkaline media, with only small overpotentials of 270 and 94 mV at a current density of 10 mA cm, respectively. The good performance was attributed to abundant active sites and high electrical conductivity of the bimetallic nitrides and efficient mass transport of the 3D r-GO aerogel framework. Furthermore, an alkaline electrolyzer was set up using NiFeN/r-GO as both the cathode and the anode, which achieved a 10 mA cm current density at 1.60 V with durability of 100 h for overall water splitting. Density functional theory calculations support that NiFeN (111)/r-GO is more favorable for overall water splitting since the surface electronic structure of NiFeN is tuned by transferring electrons from NiFeN cluster to the r-GO through interaction of two metal species. Thus, the currently developed NiFeN/r-GO with superior water-splitting performance may potentially serve as a material for use in industrial alkaline water electrolyzers.

Hydrated electron (e) induced reduction techniques are promising for decomposing recalcitrant organic pollutants. However, its vigorous reactivity with copresent scavenging species and the difficulty in minimizing the competitive reactions make the proportion of e participating in pollutant decomposition low, reflecting by slow decomposition kinetics. In this study, a high photon flux UV/sulfite system was employed to promote e production. Its feasibility in enhancing a notorious recalcitrant pollutant, PFOS, decomposition was investigated. The effective photon flux utilized for producing e was 9.93 × 10 einstein/cm·s. At initial solution pH 9.2, with DO about 5 mg/L, and at around 25 °C, 98% PFOS was decomposed within 30 min from its initial concentration of 32 μM. The k of PFOS decomposition was 0.118 min (7.08 h), and about 8-400 folds faster than those obtained in other reductive approaches. In this system, PFOS decomposition showed can tolerate copresent 7 mg N/L of NO. Suggested by molecular orbitals and thermodynamic analyses, the mechanisms responsible for PFOS decomposition involve defluorination, desulfonation, and centermost C-C bond scission. By demonstrating a more practical relevant treatment process, the outcomes of this study would be helpful for facilitating future applications of e induced reduction techniques for efficient recalcitrant pollutants decomposition.

The application of MOF materials in photovoltaic devices is comprehensively summarized and discussed.

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Atomic interface regulation that can efficiently optimize the performance of single‐atom catalysts (SACs) is a worthwhile research topic. The challenge lies in deeply understanding the structure–properties correlation based on control of the coordination chemistry of individual atoms. Herein, a new kind of W SACs with oxygen and nitrogen coordination (W‐NO/NC) and a high metal loading over 10 wt% is facilely prepared by introducing an oxygen‐bridged [WO4] tetrahedron. The local structure and coordination environment of the W SACs are confirmed by high‐angle annular dark‐field scanning transmission electron microscopy, X‐ray photoelectron spectroscopy, and extended X‐ray absorption fine structure. The catalyst shows excellent selectivity and activity for the electrochemical nitrogen reduction reaction (NRR). Density functional theory calculation reveals that unique electronic structures of the N and O dual‐coordinated W sites optimize the binding energy of the NRR intermediate, resulting in facilitating the electrocatalytic NRR. This work opens an avenue toward exploring the correlation between coordination structure and properties.

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Poly(N‐isopropylacrylamide)‐block‐poly{6‐[4‐(4‐methylphenyl‐azo) phenoxy] hexylacrylate} (PNIPAM‐b‐PAzoM) was synthesized by successive reversible addition‐fragmentation chain transfer (RAFT) polymerization. In H2O/THF mixture, amphiphilic PNIPAM‐b‐PAzoM self‐assembles into giant micro‐vesicles. Upon irradiation of light at 365 nm, fusion of the vesicles was observed directly under an optical microscope. The real‐time fusion process is presented and the derivation is preliminarily due to the perturbation by the photoinduced trans‐to‐cis isomerization of azobenzene units in the vesicles.magnified image

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