Material interfaces permit electron transfer that modulates the electronic structure and surface properties of catalysts,leading to radically enhanced rates for many important reactions.Unlike conventional thoughts,the nanoscale interfacial interactions have been recently envisioned to be able to afect the reactivity of catalysts far from the interface.However,demonstration of such unlocalized alterations in existing interfacial materials is rare,impeding the development of new catalysts.We report the observation of unprecedented long-range activation of polydymite Ni_(3)S_(4) nanorods through the interfacial interaction created by PdS_(x) nanodots(dot-on-rod structure)for high-performance water catalytic electroreduction.Experimental results show that this local interaction can activate Ni3S4 rods with length even up to 25 nanometers due to the tailored surface electronic structure.We anticipate that the long-range efect described here may be also applicable to other interfacial material systems,which will aid the development of newly advanced catalysts for modern energy devices.
Although nickel-based catalysts display good catalytic capability and excellent corrosion resistance under alkaline electrolytes for water splitting,it is still imperative to enhance their activity for real device applications.Herein,we decorated Ni0.85Se hollow nanospheres onto reduced graphene oxide(RGO)through a hydrothermal route,then annealed this composite at different temperatures(400℃,NiSe2-400 and 450℃,NiSe2-450)under argon atmosphere,yielding a kind of NiSe2/RGO composite catalysts.Positron annihilation spectra revealed two types of vacancies formed in this composite catalyst.We found that the NiSe2-400 catalyst with dual Ni-Se vacancies is able to catalyze the oxygen evolution reaction(OER)efficiently,needing a mere 241 mV overpotential at 10 mA·cm−2.In addition,this catalyst exhibits outstanding stability.Computational studies show favorable energy barrier on NiSe2-400,enabling moderate OH−adsorption and O2 desorption,which leads to the enhanced energetics for OER.
