Atomistic Dipolar Catalysis: Rules for Catalyst Polarization, Reactant Activation and Conversion

As the extremely-sized nanocrystals and nanopores, an adatom (M) and atomic vacancy (V0) exhibit extraordinary catalysis capability, yet understanding the catalyst-reactant interfacial bonding and electronic dynamics remains a challenge. With the aid of density functional theory calculations, we examined the dehydrogenization of CH4 catalyzed using Rh(111;100), W(110), Ru(0001) surfaces, and monolayer graphene, with and without M or V0 as prototypes to prove the concept of atomistic dipolar catalysis (ADC) that unifies the effects of atomic under- and hetero-coordination. Results confirmed that the three-stage ADC follows the respective regulations: First, atomic irregular coordination creates atomistic MP and vacancy V0 dipoles generating stronger local electric fields; second, the interplay of the (X = MP/V0):H attraction and X:C repulsion at the X:H–C interface activates the reactant by stretching the H–C bond, with the “:” denoting the negative pole of the X; and finally, the efficiency of the reactant conversion depends on the charge quantity of the X dipoles. The development should impact on devising efficient catalysts and provide deeper insight into ADC bonding and electronic dynamics.