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Developing chiral electrode catalysts for enantioselective electrosynthesis is a great challenge, as it requires catalysts that possess both high activity and enantioselectivity. Precise synthesis of nanoclusters and single atoms coexisting chiral catalysts provide a promising pathway for enhancing asymmetric catalytic performance. Herein, chiral electrode catalysts are fabricated comprising gold clusters (R‐AuC) and single atoms (R‐AuS) on graphene oxide (R‐AuC/S@GO) through an assembly‐irradiation strategy. Thereinto, the R‐Aus is in situ generated from R‐AuC under light irradiation. The monoatomization process can be precisely regulated by changing the wavelength of the light, resulting in four Au‐based chiral electrode (R‐Au@GO) catalysts with different ratios of nanoclusters and single atoms. These chiral electrodes are applied in the electrocatalytic enantioselective hydrogenation of methyl benzoylformate (MB) to chiral methyl mandelate (S‐MM), and the R‐AuC/S‐2@GO with ≈26% R‐AuC and 74% R‐AuS achieve the highest catalytic activity (35 µmol cm−2 h−1 productivity) and enantioselectivity [97% enantiomeric excess (ee)]. Detailed experimental analysis and density functional theory calculations reveal that the R‐AuS on GO promotes the in situ generation of H* species, and R‐AuC mainly drives the enantioselective conversion of MB by transferring the H* species to the carbonyl group of MB, ultimately yielding chiral S‐MM. [ABSTRACT FROM AUTHOR]

This study conducts hydrothermal leaching of commercial LiFePO4 (LFPO) cathode materials with oxalic acid, citric acid, or glycine without any other oxidants or reductants. Of these acids, glycine exhibits the weakest leaching behavior, with the leaching efficiency of lithium (Li), iron (Fe), or phosphorus (P) less than 15% even at 200 °C and an acid concentration of 0.8 mol L−1 for 10 min. For oxalic acid, at 200 °C for 10 min, with a pulp density of 30 g L−1 and an acid concentration of 0.8 mol L−1, the leaching efficiencies for Li and P are 100% and 97%, respectively, and 98.5% of Fe precipitates as iron oxalate (FeC2O4) that can be used as a precursor for preparing LFPO cathode materials. Citric acid shows the highest leaching efficiency for Li, Fe, and P, reaching 96%, 100%, and 88%, respectively, at 90 °C for 10 min with a pulp density of 10 g L−1 and an acid concentration of 0.8 mol L−1. The continuous hydrothermal leaching of LFPO cathode materials with citric acid is first achieved. These results clarify the superiority of citric acid over oxalic acid and glycine with respect to the leaching efficiency for Li, Fe, and P from LFPO batteries under hydrothermal conditions. [ABSTRACT FROM AUTHOR]

Conventional adhesives often emit volatile organic compounds (VOCs), which have a negative impact on human health. In this paper, an environmentally‐friendly supramolecular adhesive PD which has high adhesive and low VOCs emission is prepared by the reaction between polyethyleneimine (PEI) and 3,4‐dihydroxybenzaldehyde (DBA). PD containing abundant catechol groups exhibit excellent adhesion to wood substrates and is able to reach a maximum shear strength of 5.20 ± 0.39 MPa. One factor is attributed to multiple reactions between PEI, and DBA and oxidation of DBA. These reactions construct a complex three‐dimensional cross‐linked structure which is very helpful to improve the bonding performance of the adhesive. Another reason refers to the fact that a large number of catechol groups in PD can form a lot of hydrogen bonds with the amino group in PEI and the hydroxyl group in the wood substrate. These hydrogen bonds play an important role in enhancing shear strength. PD adhesives have a stronger bond strength than commercial chloroprene rubber (CR, Pattex‐PXL) and polyvinyl acetate adhesives (PVAc, JUJU‐8708) and have lower emissions of VOCs. As an environmentally‐friendly adhesive for wood‐based substrates, this adhesive may have potential applications in the wood processing industry. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Block copolymers not only combine properties of different segments but also generate new application prospects. Poly(α‐amino acid)‐b‐poly(tetrahydrofuran)‐b‐poly(α‐amino acid) (PAA‐PTHF‐PAA) is one of the copolymers. In this contribution, di‐hydroxyl‐ended HO‐PTHF‐OH is transferred into di‐oxyamino‐ended H2NO‐PTHF‐ONH2 quantitatively, which is used as a macroinitiator to polymerize sarcosine N‐thiocarboxyanhydride (Sar‐NTA) and N‐phenyoxycarbonyl N‐ε‐carbobenzyloxy‐D‐lysine (ZDL‐NPC). Well‐defined triblock PAA‐NHO‐PTHF‐ONH‐PAA is produced with high molecular weight (up to 25.3 kg/mol) and narrow dispersity. The amphiphilic PSar‐NHO‐PTHF‐ONH‐PSar (STS) self‐assembles into micelles with uniform diameters of 30—40 nm according to DLS. Owing to oxygen amide groups inside the backbone of these copolymers, the polyether‐poly(amino acid)s block copolymers are cleavable under an acidic environment and therefore have potential applications in smart biomedicine and engineering. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Block copolymers not only combine properties of different segments but also generate new application prospects. Poly(α‐amino acid)‐b‐poly(tetrahydrofuran)‐b‐poly(α‐amino acid) (PAA‐PTHF‐PAA) is one of the copolymers. In this contribution, di‐hydroxyl‐ended HO‐PTHF‐OH is transferred into di‐oxyamino‐ended H2NO‐PTHF‐ONH2 quantitatively, which is used as a macroinitiator to polymerize sarcosine N‐thiocarboxyanhydride (Sar‐NTA) and N‐phenyoxycarbonyl N‐ε‐carbobenzyloxy‐D‐lysine (ZDL‐NPC). Well‐defined triblock PAA‐NHO‐PTHF‐ONH‐PAA is produced with high molecular weight (up to 25.3 kg/mol) and narrow dispersity. The amphiphilic PSar‐NHO‐PTHF‐ONH‐PSar (STS) self‐assembles into micelles with uniform diameters of 30—40 nm according to DLS. Owing to oxygen amide groups inside the backbone of these copolymers, the polyether‐poly(amino acid)s block copolymers are cleavable under an acidic environment and therefore have potential applications in smart biomedicine and engineering. [ABSTRACT FROM AUTHOR]