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Near‐infrared light‐emitting diodes (NIR LEDs) based on perovskite quantum dots (QDs) have produced external quantum efficiency (EQE) of ~15 %. However, these high‐performance NIR‐QLEDs suffer from immediate carrier quenching because of the accumulation of migratable ions at the surface of the QDs. These uncoordinated ions and carriers—if not bound to the nanocrystal surface—serve as centers for exciton quenching and device degradation. In this work, we overcome this issue and fabricate high‐performance NIR QLEDs by devising a ligand anchoring strategy, which entails dissolving the strong‐binding ligand (Guanidine Hydroiodide, GAI) in the mediate‐polar solvent. By employing the dye‐sensitized device structure (phosphorescent indicator), we demonstrate the elimination of the interface defects. The treated QDs films exhibit an exciton binding energy of 117 meV: this represents a 1.5‐fold increase compared to that of the control (74 meV). We report, as a result, the NIR QLEDs with an EQE of 21 % which is a record among NIR perovskite QLEDs. These QLEDs also exhibit a 7‐fold higher operational stability than that of the best previously reported NIR QLEDs. Furthermore, we demonstrate that the QDs are compatible with large‐area QLEDs: we showcase 900 mm2 QLEDs with EQE approaching 20 %. [ABSTRACT FROM AUTHOR]

Transformation of carbon dioxide and nitrate ions into urea offers an attractive route for both nitrogen fertilizer production and environmental remediation. However, achieving this transformation under mild conditions remains challenging. Herein, we report an efficient photoelectrochemical method for urea synthesis by co‐reduction of carbon dioxide and nitrate ion over a Cu2O photocathode, delivering urea formation rate of 29.71±2.20 μmol g−1 h−1 and Faradaic efficiency (FE) of 12.90±1.15 % at low external potential (−0.017 V vs. reversible hydrogen electrode). Experimental data combined with theoretical calculations suggest that the adsorbed CO* and NO2* species are the key intermediates, and associated C−N coupling is the rate‐determining step. This work demonstrates that Cu2O is an efficient catalyst to drive co‐reduction of CO2 and NO3− to urea under light irradiation with low external potential, showing great opportunity of photoelectrocatalysis as a sustainable tool for value‐added chemical synthesis. [ABSTRACT FROM AUTHOR]

Electrocatalytic upgrading of wasted plastic and renewable biomass represents a sustainable method to produce chemicals but is limited to carbohydrates, leaving other value‐added chemicals, such as organonitrogen compounds, being scarcely explored. Herein, we reported an electrocatalytic oxidation strategy to transform polyethylene terephthalate (PET) plastic‐derived ethylene glycol (EG) and biomass‐derived polyols into formamide, in the presence of ammonia (NH3) over a tungsten oxide (WO3) catalyst. Taking EG‐to‐formamide as an example, we achieved a high formamide productivity of 537.7 μmol cm−2 h−1 with FE of 43.2 % at a constant current of 100 mA cm−2 in a flow electrolyzer with 12‐h test, representing a more advantageous performance compared with previous reports for formamide electrosynthesis. Mechanistic understanding revealed that the cleavage of the C−C bond in the EG was facilitated by nucleophilic attack of in situ formed nitrogen radicals from NH3, with resultant C−N bond construction and eventually formamide production. Furthermore, this strategy can be extended to transformation of PET bottle and a series of biomass‐derived polyols with carbon number from three (glycerol) to six (glucose), producing formamide with high efficiencies. This work demonstrates a sustainable upgrading strategy of plastic and biomass that may have implications to more value‐added chemicals production beyond carbohydrates. [ABSTRACT FROM AUTHOR]

Due to the superior catalytic activity and efficient utilization of noble metals, nanocatalysts are extensively used in the modern industrial production of chemicals. The surface structures of these materials are significantly influenced by reactive adsorbates, leading to dynamic behavior under experimental conditions. The dynamic nature poses significant challenges in studying the structure–activity relations of catalysts. Herein, we unveil an anomalous entropic effect on catalysis via surface pre‐melting of nanoclusters through machine learning accelerated molecular dynamics and free energy calculation. We find that due to the pre‐melting of shell atoms, there exists a non‐linear variation in the catalytic activity of the nanoclusters with temperature. Consequently, two notable changes in catalyst activity occur at the respective temperatures of melting for the shell and core atoms. We further study the nanoclusters with surface point defects, i.e. vacancy and ad‐atom, and observe significant decrease in the surface melting temperatures of the nanoclusters, enabling the reaction to take place under more favorable and milder conditions. These findings not only provide novel insights into dynamic catalysis of nanoclusters but also offer new understanding of the role of point defects in catalytic processes. [ABSTRACT FROM AUTHOR]

Nucleophilic substitutions are fundamentally important transformations in synthetic organic chemistry. Despite the substantial advances in bimolecular nucleophilic substitutions (SN2) at saturated carbon centers, analogous SN2 reaction at the amide nitrogen atom remains extremely limited. Here we report an SN2 substitution method at the amide nitrogen atom with amine nucleophiles for nitrogen–nitrogen (N−N) bond formation that leads to a novel strategy toward biologically and medicinally important hydrazide derivatives. We found the use of sulfonate‐leaving groups at the amide nitrogen atom played a pivotal role in the reaction. This new N−N coupling reaction allows the use of O‐tosyl hydroxamates as electrophiles and readily available amines, including acyclic aliphatic amines and saturated N‐heterocycles as nucleophiles. The reaction features mild conditions, broad substrate scope (>80 examples), excellent functional group tolerability, and scalability. The method is applicable to late‐stage modification of various approved drug molecules, thus enabling complex hydrazide scaffold synthesis. [ABSTRACT FROM AUTHOR]

The renewable‐electricity‐driven CO2 reduction to formic acid would contribute to establishing a carbon‐neutral society. The current catalyst suffers from limited activity and stability under high selectivity and the ambiguous nature of active sites. Herein, we report a powerful Bi2S3‐derived catalyst that demonstrates a current density of 2.0 A cm−2 with a formate Faradaic efficiency of 93 % at −0.95 V versus the reversible hydrogen electrode. The energy conversion efficiency and single‐pass yield of formate reach 80 % and 67 %, respectively, and the durability reaches 100 h at an industrial‐relevant current density. Pure formic acid with a concentration of 3.5 mol L−1 has been produced continuously. Our operando spectroscopic and theoretical studies reveal the dynamic evolution of the catalyst into a nanocomposite composed of Bi0 clusters and Bi2O2CO3 nanosheets and the pivotal role of Bi0−Bi2O2CO3 interface in CO2 activation and conversion. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 (CO2RR) into high value‐added chemicals is an attractive route to achieve carbon neutrality. However, the development of an efficient catalyst for CO2RR is still largely by trial‐and‐error and is very time‐consuming. Herein, we built an electrocatalyst testing platform featuring a home‐built automatic flow cell to accelerate the discovery of efficient catalysts. A fast screening of 109 Cu‐based bimetallic catalysts in only 55 h identifies Mg combined with Cu as the best electrocatalyst for CO2 to C2+ products. The thus designed Mg−Cu catalyst achieves a Faradaic efficiency (FE) of C2+ products up to 80 % with a current density of 1.0 A cm−2 at −0.77 V versus reversible hydrogen electrode (RHE). Systematic experiments with in situ spectroelectrochemistry analyses show that Mg2+ species stabilize Cu+ sites during CO2RR and promote the CO2 activation, thus enhancing the *CO coverage to promote C−C coupling. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of biomass‐derived 5‐hydroxymethylfurfural (HMF) represents an elegant route toward sustainable value‐added chemicals production that circumvents the use of fossil fuel and hydrogen. However, the reaction efficiency is hampered by the high voltage and low activity of electrodes (Cu, Bi, Pb). Herein, we report a Ru1Cu single‐atom alloy (SAA) catalyst with isolated Ru atoms on Cu nanowires that exhibits an electrochemical reduction of HMF to 2,5‐dihydroxymethylfuran (DHMF) with promoted productivity (0.47 vs. 0.08 mmol cm−2 h−1) and faradic efficiency (FE) (85.6 vs. 71.3 %) at −0.3 V (vs. RHE) compared with Cu counterpart. More importantly, the FE (87.5 %) is largely retained at high HMF concentration (100 mM). Kinetic studies by using combined electrochemical techniques suggest disparate mechanisms over Ru1Cu and Cu, revealing that single‐atom Ru promotes the dissociation of water to produce H* species that effectively react with HMF via an electrocatalytic hydrogenation (ECH) mechanism. [ABSTRACT FROM AUTHOR]

Heterogeneous Catalysis. In their Communication (e202405379), Jun Cheng et al. use machine learning molecular dynamics to demonstrate anomalous entropic effect on catalysis via surface pre‐melting of nanoclusters...By Fu‐Qiang Gong; Yun‐Pei Liu; Ye Wang; Weinan E; Zhong‐Qun Tian and Jun ChengReported by Author; Author; Author; Author; Author; Author [Extracted from the article]

Electrocatalytic CO2 reduction to CO emerges as a potential route of utilizing emitted CO2. Metal‐N‐C hybrid structures have shown unique activities, however, the active centers and reaction mechanisms remain unclear because of the ambiguity in true atomic structures for the prepared catalysts. Herein, combining density‐functional theory calculations and experimental studies, the reaction mechanisms for well‐defined metal–N4 sites were explored using metal phthalocyanines as model catalysts. The theoretical calculations reveal that cobalt phthalocyanine exhibits the optimum activity for CO2 reduction to CO because of the moderate *CO binding energy at the Co site, which accommodates the *COOH formation and the *CO desorption. It is further confirmed by experimental studies, where cobalt phthalocyanine delivers the best performance, with a maximal CO Faradaic efficiency reaching 99 %, and maintains stable performance for over 60 hours. To the "CO2RR": Metal phthalocyanines (MePcs) with well‐defined metal–N4 structures were used as model catalysts to study the active centers and reaction mechanisms for the electrocatalytic CO2 reduction reaction (CO2RR). Theoretical and experimental studies identify CoPc as the optimum catalyst for the selective electrocatalytic CO2RR to deliver CO. The Co site serves as the active center for achieving a Faradaic efficiency (FE) of up to 99 % with long‐term stability. [ABSTRACT FROM AUTHOR]

The epitranscriptomic mark N6‐methyladenosine (m6A) is the most abundant RNA modification in eukaryotic mRNA, but various limitations in currently available m6A detection methods have precluded routine identification of m6A marks at the single‐site level in mRNA transcripts. Herein, we report a single‐base elongation‐ and ligation‐based qPCR amplification method (termed "SELECT") that exploits the ability of m6A to hinder 1) the single‐base elongation activity of DNA polymerases and 2) the nick ligation efficiency of ligases; SELECT employs qPCR for quantitation. Following optimization and validation, SELECT was applied on three highly relevant proof‐of‐concept cases: determining 1) if a putative m6A site is m6A‐modified in mRNAs and lncRNAs from biological samples, 2) the m6A fraction at biological sites, and 3) if a particular m6A modification enzyme functions on a specific target site. In summary, the rapid and flexible SELECT method facilitates the identification and verification of m6A marks with unprecedented ease. Identifying m6A: A radiolabeling‐free method enables the rapid detection of N6‐methyladenosine (m6A) in rRNA, lncRNA, and mRNA with single‐base resolution. It exploits the ability of m6A to hinder the single‐base elongation activity of DNA polymerases and the nick ligation efficiency of ligases. [ABSTRACT FROM AUTHOR]

Flow chemistry, massarinolin A, photochemistry, purpurolide, total synthesis Keywords: flow chemistry; massarinolin A; photochemistry; purpurolide; total synthesis EN flow chemistry massarinolin A photochemistry purpurolide total synthesis 24730 24730 1 11/10/21 20211115 NES 211115 B Massarinolin A b and the purpurolides are bioactive bergamotane sesquiterpenes containing a complex tetracyclic skeleton. Inside Cover: Flow Chemistry-Enabled Divergent and Enantioselective Total Syntheses of Massarinolin A, Purpurolides B, D, E, 2,3-Deoxypurpurolide C, and Structural Revision of Massarinolin A (Angew. [Extracted from the article]