Exploring highly efficient nanocatalysts for hydrogen (H 2 ) production from catalytic hydrolysis of ammonia borane (AB) under ambient conditions and further unveiling their catalytic mechanism are of critical importance for renewable energy conversion technologies but remain big challenges. Herein, ultrafine binary RuP alloy nanoclusters homogeneously encapsulated onto nitrogen-functionalized hollow mesoporous carbon supports (RuP@NHMCs) are reported as a high-performance platinum (Pt)free nanocatalyst for catalytic hydrolysis of AB at room temperature. Remarkable catalytic activity with a very high turnover frequency of 1774 mol H 2 mol Ru −1 min −1 and a low activation energy of 36.3 kJ mol −1 is observed based on compositional and structural synergies of RuP@NHMCs. Results of control experiments and catalytic kinetics studies reveal that the rate-determining step of catalytic hydrolysis of AB is the oxidation cleavage of a covalently stable H−OH bond, while RuP@NHMCs result in multiple electronic, functional, size, and support effects that kinetically accelerate the cleavage of attacked H− OH. Furthermore, RuP@NHMCs exhibit a good catalytic activity with a high yield of >99% for tandem hydrogenation of nitroarenes coupled with the hydrolysis of AB. We strongly believe that the catalyst design principle reported here could provide a new opportunity for synthesizing other Pt-free high-performance nanocatalysts.
Engineering crystalline structures/defects and elemental compositions is synthetically critical to optimize surface features of noble metal nanocrystals and thus improve their catalytic performances in various reactions. In this manuscript, we report a facile one-step aqueous synthesis of onedimensional (1D) noble metal−metalloid alloy nanowires (NWs) with an ultrathin and wavy morphology, controlled crystalline defects, and binary PdB compositions as a highly efficient catalyst toward the electrochemical ethanol oxidation reaction (EOR). We show that the utilization of hexadecylpyridinium chloride as functional surfactant is of great importance to confine in-thecolumnar epitaxial nucleation of anisotropic ultrathin PdB NWs, while the attachment growth precisely controls their surface crystalline defects with a wavy morphology. Meanwhile, this strategy is synthetically universal and can be readily extended to engineer an ultrathin wavy morphology and crystalline defect of ternary PdMB (M = Cu and Pt) alloy NWs. Owing to multiple structural and compositional merits, resultant PdB alloy NWs synergistically expose more electrocatalytically active sites and also kinetically accelerate the removal of CO-related poisons, remarkably improving electrocatalytic EOR activity and stability compared to their counterpart catalysts. Besides, wavy PdB alloy NWs are also electrochemically more active for electrocatalytic oxidation of other alcohols (methanol, glycerol, and glucose). The findings reported here thus shed a bright light on rational design of the high-performance metal alloy catalysts for their potential applications in fine chemical synthesis, fuel cells, and beyond.
Ternary noble metal-metalloid-nonmetal
PdBS alloy mesoporous nanospheres
(MSs) with three-dimensional central-radial pore channels were prepared
for an electrocatalytic hydrogen evolution reaction. The synthesis
was performed via precise control in the reduction and nucleation
growth of ternary PdBS alloy MSs along confined cylinder mesophases
assembled by amphiphilic dioctadecyldimethylammonium chloride. The
resultant PdBS alloy MSs disclosed a remarkably improved electrocatalytic
performance due to their structural and compositional synergies. This
finding extended our knowledge on the rational design and targeted
synthesis of novel noble metal-metalloid-nonmetal alloys with desired
structures and morphologies for catalysis and other applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.