Determining the structures of nanoparticles at atomic resolution is vital to understand their structure–property correlations. Large metal nanoparticles with core diameter beyond 2 nm have, to date, eluded characterization by single-crystal X-ray analysis. Here we report the chemical syntheses and structures of two giant thiolated Ag nanoparticles containing 136 and 374 Ag atoms (that is, up to 3 nm core diameter). As the largest thiolated metal nanoparticles crystallographically determined so far, these Ag nanoparticles enter the truly metallic regime with the emergence of surface plasmon resonance. As miniatures of fivefold twinned nanostructures, these structures demonstrate a subtle distortion within fivefold twinned nanostructures of face-centred cubic metals. The Ag nanoparticles reported in this work serve as excellent models to understand the detailed structure distortion within twinned metal nanostructures and also how silver nanoparticles can span from the molecular to the metallic regime.

The nitrogenous nucleophile electrooxidation reaction (NOR) playsavital role in the degradation and transformation of available nitrogen. Focusing on the NOR mediated by the b-Ni(OH) 2 electrode,w ed ecipher the transformation mechanism of the nitrogenous nucleophile.F or the two-step NOR, proton-coupled electron transfer (PCET) is the bridge between electrocatalytic dehydrogenation from b-Ni(OH) 2 to b-Ni(OH)O,a nd the spontaneous nucleophile dehydrogenative oxidation reaction. This theory can give ag ood explanation for hydrazine and primary amine oxidation reactions,but is insufficient for the urea oxidation reaction (UOR). Through operando tracing of bond rupture and formation processes during the UOR, as well as theoretical calculations,wepropose apossible UOR mechanism whereby intramolecular coupling of the N À Nb ond, accompanied by PCET,hydration and rearrangement processes,results in high performance and ca. 100 %N 2 selectivity.T hese discoveries clarify the evolution of nitrogenous molecules during the NOR, and they elucidate fundamental aspects of electrocatalysis involving nitrogen-containing species.

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A surface molecular imprinting polymer (SMIP) with doxorubicin (DOX) as the template was prepared on the surface of mesoporous silica nanoparticles (MSNs), which were further used as DOX carriers. The loading amount of DOX was calculated as 10.5±0.2 wt% with loading efficiency of 70±8%. The DOX release was controlled because the monomer molecule used in polymerization of SMIP containing sulfur-sulfur bonding, which could be decomposed with an acidic pH and glutathione (GSH). Under an acidic pH and high concentration of GSH, there was greater release of DOX than under normal physiological conditions, which induced less damage to normal cells than to cancer cells. Confocal laser scanning microscopy studies verified the invasion of the DOX within SMIP into TCA8113 cancer cells. These results indicate that the prepared SMIP was an effective nanocarrier.

The nitrogenous nucleophile electrooxidation reaction (NOR) plays a vital role in the degradation and transformation of available nitrogen. Focusing on the NOR mediated by the β‐Ni(OH)2 electrode, we decipher the transformation mechanism of the nitrogenous nucleophile. For the two‐step NOR, proton‐coupled electron transfer (PCET) is the bridge between electrocatalytic dehydrogenation from β‐Ni(OH)2 to β‐Ni(OH)O, and the spontaneous nucleophile dehydrogenative oxidation reaction. This theory can give a good explanation for hydrazine and primary amine oxidation reactions, but is insufficient for the urea oxidation reaction (UOR). Through operando tracing of bond rupture and formation processes during the UOR, as well as theoretical calculations, we propose a possible UOR mechanism whereby intramolecular coupling of the N−N bond, accompanied by PCET, hydration and rearrangement processes, results in high performance and ca. 100 % N2 selectivity. These discoveries clarify the evolution of nitrogenous molecules during the NOR, and they elucidate fundamental aspects of electrocatalysis involving nitrogen‐containing species.