Electronic Metal–Support Interaction To Modulate MoS₂-Supported Pd Nanoparticles for the Degradation of Organic Dyes

Electronic modulation of heterogeneous metal catalysts has been considered as an effective means to optimize their catalytic performance. Two-dimensional nanomaterials, typically used as the supporting substrates for anchoring the active metal nanoparticles, are well-known to profoundly influence the electronic structure of metals through interfacial electronic metal–support interaction (EMSI). However, the detailed investigation of EMSI for catalytic enhancement still remains obscure at the microscopic level. Herein, we propose to utilize MoS2 nanosheets to modulate the electronic structure of Pd through EMSI and investigate the influence of “support effect” of MoS2 on the catalytic activity of Pd utilizing degradation of methylene blue (MB) with the electron donor NaBH4 as a simple model reaction. Mechanistic investigations reveal that the electron transfer from Pd to MoS2 makes a highly electron-deficient Pd surface. During the target catalysis, this interfacial electronic structure makes the surface of Pd favor the adsorption of electron-rich reactants (for example, NaBH4), accelerating the electron transfer from NaBH4 to MB. Our finding promises an effective and facile strategy for catalyst design and sheds more insights into the structure–activity relationship of supported metal catalysts in general.