Atomically dispersed Zn–N–C nanomaterials are promising platinum‐free catalysts for the oxygen reduction reaction (ORR). However, the fabrication of Zn–N–C catalysts with a high Zn loading remains a formidable challenge owing to the high volatility of the Zn precursor during high‐temperature annealing. Herein, we report that an atomically dispersed Zn–N–C catalyst with an ultrahigh Zn loading of 9.33 wt % could be successfully prepared by simply adopting a very low annealing rate of 1° min−1. The Zn–N–C catalyst exhibited comparable ORR activity to that of Fe–N–C catalysts, and significantly better ORR stability than Fe–N–C catalysts in both acidic and alkaline media. Further experiments and DFT calculations demonstrated that the Zn–N–C catalyst was less susceptible to protonation than the corresponding Fe–N–C catalyst in an acidic medium. DFT calculations revealed that the Zn–N4 structure is more electrochemically stable than the Fe–N4 structure during the ORR process.

Modifying the interfaces of CH3NH3PbI3 with TiO2 and hole transport layers using two different types of thiols leads to enhanced performance and stability of perovskite solar cells. The incorporation of HOOC-Ph-SH at the TiO2/perovskite interface facilitates electron transfer from perovskite to TiO2 and also alters the morphology of perovskite crystal growth to increase the power conversion efficiency. The modification of pentafluorobenzenethiol at the perovskite/hole transport layer interface improves the stability.

Controllable synthesis of single atom catalysts (SACs) with high loading remains challenging due to the aggregation tendency of metal atoms as the surface coverage increases. Here we report the synthesis of graphene supported cobalt SACs (Co1/G) with a tuneable high loading by atomic layer deposition. Ozone treatment of the graphene support not only eliminates the undesirable ligands of the pre-deposited metal precursors, but also regenerates active sites for the precise tuning of the density of Co atoms. The Co1/G SACs also demonstrate exceptional activity and high selectivity for the hydrogenation of nitroarenes to produce azoxy aromatic compounds, attributable to the formation of a coordinatively unsaturated and positively charged catalytically active center (Co–O–C) arising from the proximal-atom induced partial depletion of the 3d Co orbitals. Our findings pave the way for the precise engineering of the metal loading in a variety of SACs for superior catalytic activities.

The selective adsorption of a corrosive gas, SO 2 , into two microporous pillared paddle-wheel frameworks M(bdc)(ted) 0.5 [M = Ni, Zn; bdc = 1,4-benzenedicarboxylate; ted = triethylenediamine] is studied by volumetric adsorption measurements and a combination of in-situ infrared spectroscopy and ab initio density functional theory (DFT) calculations. The uptake of SO 2 in M(bdc)(ted) 0.5 at room temperature is quite significant, 9.97 mol/kg at 1.13 bar. The major adsorbed SO 2 molecules contributing to the isotherm measurements are characterized by stretching bands at 1326 and 1144 cm -1 . Theoretical calculations including van der Waals interactions (based on vdW-DF) suggest that two adsorption configurations are possible for these SO 2 molecules. One geometry involves an SO 2 molecule bonded through its sulfur atom to the oxygen atom of the paddle-wheel building unit and its two oxygen atoms to the C-H groups of the organic linkers by formation of hydrogen bonds. Such a configuration results in a distortion of the benzene rings, which is consistent with the experimentally observed shift of the ring deformation mode. In the other geometry, SO 2 establishes hydrogen bonding with -CH 2 group of the ted linker through its two oxygen atoms simultaneously. The vdW-DF-simulated frequency shifts of the SO 2 stretching bands in these two configurations are similar and in good agreement with spectroscopically measured values of physisorbed SO 2 . In addition, the IR spectra reveal the presence of another minor species, characterized by stretching modes at 1242 and 1105 cm -1 and causing significant perturbations of MOFs vibrational modes (CH x and carboxylate groups). This species is more strongly bound, requiring a higher temperature (~150 °C) to remove it than for the main physisorbed species. The adsorption configurations of SO 2 into M(bdc)(ted) 0.5 derived by infrared spectroscopy and vdW-DF calculations provide the initial understanding to develop microporous metal organic frameworks materials based on paddlewheel secondary-building units for SO 2 removal in industrial processes.