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Atomically dispersed metal catalysts maximize atom e ciency and display unique catalytic properties compared to regular metal nanoparticles. However, achieving high reactivity while still preserving high stability at high loadings remains as a grand challenge. Here we solve the challenge by synergizing strong metal-support interactions and spatial con nement, which enable to fabricate highly loaded (3.1 wt%), active and stable atomic Ni and dense atomic Cu grippers (8.1 wt%) on a graphitic C 3 N 4 support.For semi-hydrogenation of acetylene in excess of ethylene, the fabricated catalyst shows 11 times higher activity than the atomic Ni alone, high ethylene selectivity (90%), and high stability against both sintering and coke formation for 350 h. Comprehensive microscopic and spectroscopic characterization and theoretical calculations reveal the active site of the bridging Ni con ned in two hydroxylated Cu grippers, whose structure changes dynamically by breaking interfacial Ni-support bonds upon reactant adsorption and making these bonds upon product desorption. Such a dynamic effect confers high activity/selectivity and high stability, providing an avenue to rational design of e cient, stable, highly loaded, yet atomically dispersed catalysts.

Site-selective blocking by ALD disentangles the geometric and electronic effects of catalysts beyond the selectivity volcano.

A Co-based metal-organic framework, ZIF-67, has been exploited as a self-template to afford N-doped porous carbon incorporating Co NPs with surface-oxidized CoO species, which exhibit excellent catalytic activity, selectivity and magnetic recyclability toward the direct oxidation of alcohols to esters with O2 as a benign oxidant under mild conditions.

A 3D current collector made of covalently connected carbon nanostructures is presented, which can significantly improve battery performance when used as the cathode and/or anode. A Li-S cell assembled using these current collectors, with the cathode loaded with elemental sulfur and the anode loaded with lithium metal, delivers a high-rate capacity of 860 mA h g at 12 C.

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Herein, we report the construction of a novel hydrolase model via self-assembly of a synthetic amphiphilic short peptide (Fmoc-FFH-CONH 2 ) into nanotubes. The peptide-based self-assembled nanotubes (PepNTs-His) with imidazolyl groups as the catalytic centers exhibit high catalytic activity for p-nitrophenyl acetate (PNPA) hydrolysis. By replacement of the histidine of Fmoc-FFH-CONH 2 with arginine to produce a structurally similar peptide Fmoc-FFR-CONH 2 , guanidyl groups can be presented in the nanotubes through the co-assembly of these two molecules to stabilize the transition state of the hydrolytic reaction. Therefore significantly improved catalytic activity has been achieved by the reasonable distribution of three dominating catalytic factors: catalytic center, binding site and transition state stabilization to the co-assembled peptide nanotubes (PepNTs-His-Arg max ). The resulting hydrolase model shows typical saturation kinetics behaviour to that of natural enzymes and the catalytic efficiency of a single catalytic center is 519-fold higher than that without catalysts. As for a nanotube with multicatalytic centers, a remarkable catalytic efficiency could be achieved with the increase of building blocks. This model suggests that the well ordered and dynamic supramolecular structure is an attractive platform to develop new artificial enzymes to enhance the catalytic activity. Besides, this novel peptidebased material has excellent biocompatibility with human cells and is expected to be applied to organisms as a substitute for natural hydrolases.