Space charge transfer is crucial for an efficient electrocatalytic process, especially for narrow-band-gap metal sulfides/selenides. Herein, we designed and synthesized a core–shell structure which is an ultrathin MoSe2 nanosheet coated CuS hollow nanoboxes (CuS@MoSe2) to form an open p–n junction structure. The space charge effect in the p–n junction region will greatly improve electron mass transfer and conduction, and also have abundant active interfaces. It was used as a bifunctional electrocatalyst for water oxidation at a wide pH range. It exhibits a low overpotential of 49 mV for the HER and 236 mV for the OER at a current density of 10 mA·cm –2 in acidic pH, 72 mV for the HER and 219 mV at 10 mA·cm –2 for the OER in alkaline pH, and 62 mV for the HER and 230 mV at 10 mA·cm –2 for the OER under neutral conditions. The experimental results and density functional theory calculations testify that the p–n junction in CuS@MoSe2 designed and synthesized has a strong space charge region with a synergistic effect. The built-in field can boost the electron transport during the electrocatalytic process and can stabilize the charged active center of the p–n junction. This will be beneficial to improve the electrocatalytic performance. This work provides the understanding of semiconductor heterojunction applications and regulating the electronic structure of active sites.

A series of aluminum complexes with Schiff base bridged indolyl ligands were synthesized as rac-lactide polymerization catalysts.

Resveratrol (3,5,4'-trihydroxylstilbene), a phytoalexin in response to injury or fungal attack, is found in grapes and other food products. It has been well documented that the compound has beneficial effects as hypolipidemic, anticancer, antiviral, neuroprotective, antiaging, and anti-inflammatory natural active principle. It was observed that both trans-and cis-resveratrols undergo hydrogen-deuterium (H/D) exchange at H-2,6 and H-4 positions of the A-ring. The exchange rates were determined by 1 H NMR spectroscopy. The results reveal that the exchange rates are configuration and pH dependent. Derivative of 2-O-β-D-glucoside can significantly speed up the H/D exchange reactions for both isomers. The trans-resveratrol experiences faster H/D exchanging than the cis-resveratrol. Such isomeric effect is possibly due to the factor that the trans-resveratrol is in favor of forming larger/super conjugative system and has less spatial interference. Theoretical calculation shows that electronegativity at these positions is in the order of H-2,6＞H-4, which is in consistent with the exchange rates observed by NMR. The results may be of help in understanding the properties of resveratrol, and in analysis of resveratrol in natural products or body fluids using mass spectroscopy that occasionally requires stable deuterium isotope labeling.

The aerobic biodegradation of dimethyl phthalate (DMP) is initiated with two hydrolysis reactions that generate an intermediate, phthalic acid (PA), that is further biodegraded through a two-step di-oxygenation reaction. DMP biodegradation is inhibited when PA accumulates, but DMP's biodegradation can be enhanced by adding an exogenous electron donor. We evaluated the effect of adding succinate, acetate, or formate as an exogenous electron donor. PA removal rates were increased by 15 and 30% for initial PA concentrations of 0.3 and 0.6 mM when 0.15 and 0.30 mM succinate, respectively, were added as exogenous electron donor. The same electron-equivalent additions of acetate and formate had the same acceleration impacts on PA removal. Consequently, the DMP-removal rate, even PA coexisting with DMP simultaneously, was accelerated by 37% by simultaneous addition of 0.3 mM succinate. Thus, lowering the accumulation of PA by addition of an electron increased the rate of DMP biodegradation.

An internal circulation baffled bioreactor was employed to realize simultaneous di-oxygenation of phthalic acid (PA) and denitrification of nitrate, which require aerobic and anoxic conditions, respectively. Adding a small concentration of succinate as an exogenous electron donor stimulated PA di-oxygenation, which produced readily oxidizable downstream products whose oxidation also enhanced denitrification of nitrate; succinate addition also stimulated denitrification. Depending on the concentration of PA, addition of 0.17 mM succinate increased the PA removal rate by 25 and 42%, while the corresponding nitrate removal rate was increased by 73 and 51%. UV/HO advanced oxidation of PA had the same effects as adding succinate, since succinate is generated by UV/HO; this acceleration effect was approximately equivalent to adding 0.17 mM succinate.

Electrocatalysts based on precious metals of Pt, Ir, Ru, and their oxides are considered to be the most effective materials for accelerating the water oxidation process, but the high cost and scarcity limited the large-scale applications. Therefore, it is necessary to develop efficient, low-cost, and durable electrocatalysts to replace precious metal catalysts. [3] As we know, in the electrocatalytic reaction of two electrons and four electrons, the activation of H 2 O and the adsorption of reaction intermediates by the active site are essential. [2b,4] For OER, the kinetic rate may be limited by the weak oxygen-binding state of the metal, and the strong bonding ability may limit the proton-electron transfer to *OH and *O. [5] On the other hand, the Volmer-Heyrovsky step will be limited by the weak or strong bonding ability during HER. [6] According to the above discussion, the adsorption capacity of the active site to reaction intermediates plays a crucial role in electrocatalytic performance, the weaker and stronger adsorption capacity will also have an adverse impact on the activity of electrocatalysis. Hence, the construction of customizable electronic structures for efficient bifunctional electrocatalysts is irresistibly attractive but still challenging.Among various electrocatalysts, metallic phthalocyanine compounds (MPc, M = Fe, Co, Ni Cu, etc.) have many advantages Implementing a molecular modulation strategy for metallic phthalocyanines (MPc) without losing the activity of the metal center and inducing a multifunction characteristic in electrocatalytic remains a challenge. Herein, a series of 2D CuCo bimetallic polymerized phthalocyanine modified with strong electron-withdrawing groups (CuCoPc-g, g = F, Cl, Br, NO 2 ) for water oxidation in the alkaline electrolyte is designed and simply synthesized. The experimental results testify that the bimetallic design can perform electronic adjustment once and introduce the second active sites to get bifunctional characteristics, and then the electronic structure of the active center can be regulated by electron-withdrawing groups for a second time to achieve the optimal state. These electrons that transfer in the active center of inner metal can generate space-charged regions and the design of the polymer can stabilize active site region to maintain long-term electrolytic stability and high activity. This study precisely regulates the electronic structure of MPc at the molecular level and provides insight into the multifunctional design of polymeric macrocyclic electrocatalysts.

The reactions of 2-N,N-dimethylamino-ethylene-imino-functionalized indolyl proligand 2-(Me 2 NCH 2 CH 2 N = CH)C 8 H 5 NH (HL) with [(Me 3 Si) 2 N] 3 RE(μ-Cl)Li(THF) 3 in toluene afforded a series of rare-earth metal amido complexes [κ 3 -(N,N,N)-2-(Me 2 NCH 2 CH 2 N = CH)C 8 H 5 N]RE[N(SiMe 3 ) 2 ] 2 (RE = Y (1a), Nd (1b), Sm (1c), Gd (1d), Dy (1e), Er (1f), and Yb (1g)). While the reaction of HL with [(Me 3 Si) 2 N] 3 Eu(μ-Cl)Li(THF) 3 produced the europium(II) complex in a dimeric form [{(η 5μ-η 1 :η 2), which is believed to have happened through the homolysis of the Eu−N bond. Further reaction of complex 1a with PhCH�NPh provided an unexpected rare-earth metal complex [κ 2 -(N,N)-PhN{PhCH(CH 2 SiMe 2 )}N(SiMe 3 )]YL (7) through the sp 3 C−H bond activation of the methyl on the silicon atom to form a Y−C bond followed by the insertion of the C�N bond of the imine PhCH�NPh to form an amido group connected to the central metal. All complexes were characterized by spectroscopic methods, elemental analyses, and single-crystal X-ray diffraction, and complexes 1a−1c and 7 were additionally characterized by NMR spectroscopy. The catalytic performance of complexes 1a−1g for the hydrosilylation of imines was investigated, and the catalytic mechanism was proposed based on the experimental results.

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