The development of active water oxidation catalysts for water splitting has stimulated considerable interest. Herein, the design and building of single atom Co sites using a supramolecular tailoring strategy are reported, that is, the introduction of pillar[4]arene[1]quinone (P4A1Q) permits mononuclear Co species stereoelectronically assembled on MoS₂ matrix to construct an atomically dispersed MoS₂@Co catalyst with modulated local electronic structure, definite chemical environment and enhanced oxygen evolution reaction performance. Theoretical calculations indicate that immsobilized single-Co sites exhibit an optimized adsorption capability of oxygen-containing intermediates, endowing the catalyst an excellent electrocatalytic oxygen evolution reaction activity, with a low overpotential of 370 mV at 10 mA cm⁻² and a small Tafel slope of 90 mV dec⁻¹. The extendable potential of this strategy to other electrocatalysts such as MoS₂@Ni and MoS₂@Zn, and other applications such as the hydrogen evolution reaction was also demonstrated. This study affords new insights into the rational design of single metal atom systems with enhanced electrocatalytic performance.

A topologically mediated synthesis of porous boron nitride aerogel has been experimentally and theoretically investigated for carbon dioxide (CO₂) uptake. Replacement of the carbon atoms in a precursor aerogel of graphene oxide and carbon nanotubes was achieved using an elemental substitution reaction, to obtain a boron and nitrogen framework. The newly prepared BN aerogel possessed a specific surface area of 716.56 m²/g and exhibited an unprecedented twentyfold increase in CO₂ uptake over N₂, adsorbing 100 cc/g at 273 K and 80 cc/g in ambient conditions, as verified by adsorption isotherms via the multipoint Brunauer-Emmett-Teller (BET) method. Density functional theory calculations were performed to give hints on the mechanism of such high selectivity of CO₂ over N₂ adsorption in BN aerogel, which may be due to the interaction between the intrinsic polar nature of B-N bonds and the high quadrupole moment of CO₂ over N₂.