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The oxygen evolution reaction (OER) remains a bottleneck for the overall water splitting. Electrocatalysts with superior activity and stability are still highly desired. Herein, a stepwise electrochemical strategy is developed to prepare Co(OH)2/NiPx nanosheet arrays with intimate and abundant heterostructures. The Co(OH)2 nanosheets, which are first electrodeposited on a blank carbon cloth electrode, serve as the substrate for the nucleation and growth of NiPx. The resultant heterointerfaces are well regulated by altering the loading of NiPx. The heterostructured Co(OH)2/NiPx with optimal NiPx loading demonstrate significantly enhanced conductivity and hydrophilicity, which greatly facilitate electron and mass transfer. In addition, strong electronic interaction between Co(OH)2 and NiPx is observed, favoring the generation of high‐valence cobalt center, thus the electrocatalytic performances toward OER are remarkably improved. The heterostructured Co(OH)2/NiPx nanosheets achieve the current density of 10 mA cm−2 at an overpotential of 236 mV, while the corresponding values for Co(OH)2 and the benchmark Ir/C are 292 and 262 mV, respectively. This study provides a facile and effective strategy to fabricate transition metal hydroxide/phosphide composite nanomaterials with intimate heterostructures, enhanced conductivity, and improved wettability, which opens a new direction for the design of highly active electrocatalysts. [ABSTRACT FROM AUTHOR]

The production of aromatic compounds from lignin is an essential issue in the transformation of biomass. Herein, a simple method has been presented for the synthesis of benzanilides and phenols from aniline involving the oxidative cleavage of β-O-4 lignin models using H2O2 as an oxidizing agent without any metal catalysts and under relatively mild conditions. [ABSTRACT FROM AUTHOR]

Using mesoporous N-doped carbons (NCs) derived from glucose and melamine as the supports, a series of Pd/NC catalysts were prepared, in which Pd nanoparticles with average size<2.0 nm were uniformly distributed on the supports. It was indicated that the resultant Pd/NC catalysts were effective for N-formylation of amines with CO2 and H2 in ethanol without any additives. Especially, the catalyst Pd/NC-800-6.9% containing quaternary N showed the best performance, affording a series of formylamides in good or even excellent yields. Further investigation reveals that the interaction between the Pd nanoparticles and quaternary nitrogen in the NC support was responsible for the good performance of the catalyst. [ABSTRACT FROM AUTHOR]

Herein the reductive amination/cyclization of levulinic acid using phenylsilane was presented to selectively produce pyrrolidones versus pyrrolidines under mild conditions by switching the catalyst from AlCl3 to RuCl3. Using AlCl3 as the catalyst, pyrrolidones were solely obtained at room temperature, while RuCl3 as the catalyst selectively afforded pyrrolidines in high yields at 45 °C. [ABSTRACT FROM AUTHOR]

Pyridine-functionalized porous organic polymers showed excellent CO2 uptake capacity (up to 63 and 171 mg g−1 at 0.1 and 1 bar at 273 K), and performed well as supports for Ru(0) nanoparticles. The resultant CarPy-CMP@Ru served as an efficient catalyst for the formylation of amines with CO2/H2, together with high product yields (89–93%), high stability and easy recyclability. [ABSTRACT FROM AUTHOR]

Ag single-atom catalysts (SACs) have great potential in selective electrocatalysis of the CO 2 reduction reaction (CO 2 RR) to CO, while it is still a challenge to achieve high current density and high atom efficiency simultaneously. Here, we present a new and simple in situ adsorption-reduction method to prepare Ag SACs supported on CeO 2 (Ag 1 /CeO 2 ). It is found that Ag single atoms are anchored on CeO 2 through strong metal-support interaction (SMSI), and each Ag atom is accompanied with three interfacial oxygen vacancies. This Ag 1 /CeO 2 exhibits high performance in the electrocatalytic CO 2 RR with a high CO faradaic efficiency (FE) of >95% under a wide potential range. The turnover frequency (TOF) value can reach 50,310 h -1 at FE CO = 99.5% in H-cells. Notably, Ag 1 /CeO 2 achieves an industrial-grade current density of 403 mA cm -2 with a high FE CO of 97.2% in flow cells. Experimental results combined with density functional theory calculation revealed that this superior performance was mainly ascribed to the existence of interfacial oxygen vacancies, which lead to the formation of Ag-O-Ce 3+ atomic interfaces, and activates the Ce 3+ -O structures as the synergistic active center of Ag, thus promoting CO 2 adsorption and activation and reducing the reaction potential barrier of *COOH-to-*CO.

As an important member of crystalline porous polymers, acylhydrazone-linked covalent organic frameworks (COFs) have gained much attention in recent years. However, the low structural stability imparts a limit on their practical applications. To tackle this problem, we report a simple strategy to increase the chemical stability of acylhydrazone-linked COFs by incorporating azobenzene groups in the conjugated framework. Through reinforcing the π-π stacking interactions between the adjacent layers with increased π-surface, it is surprising to find that the resulting materials exhibit extreme stability in harsh environments, such as in strong acid, strong base, aqueous educing agent and boiling water, even exposed to air for one year. As a proof-of-concept, such frameworks have been used to remove various organic micropollutants such as antibiotics, plastic components, endocrine disruptors, and carcinogens from water with high capacity, fast speed and excellent reusability over a wide pH range at environmentally relevant concentrations. The results provide a new avenue to significantly enhance the stability of COFs for practical applications., (© 2021 Wiley-VCH GmbH.)