In situ nanopores enrichment of Mesh-like palladium nanoplates for bifunctional fuel cell reactions: A joint etching strategy

Abundant surface structural defects can endow electrocatalysts with extraordinary physical and chemical characteristics. Herein, metastable Pd nanoparticles (NPs) with abundant twin boundaries (TBs) and atomic steps (ASs) anchored on a carbon substrate (TS‐Pd/C) are directly synthesized by a solid‐state thermal shock (TS) strategy. Molecular dynamics simulation indicates that the transient super cooling procedure after the TS synthesis can boost the formation of TBs. Benefitting from the abundant TBs and ASs, these metastable Pd NPs can serve as an advanced electrocatalyst for the ethanol oxidation reaction (EOR) with superior reactivity, stability, and CO tolerance in alkaline solutions, which far exceeds that of commercial Pd/C. The first‐principles calculations suggest that the defect structure dominated by TBs can achieve the spatial separation of the optimal adsorption sites for CO and OH. The CO can concentrate at optimal surface sites to minimize the number of poisoned active sites. The strong adsorption of OH can accelerate the EOR process and jointly promote the improvement of electrocatalytic reactivity.

Multiple Twin Boundary‐Regulated Metastable Pd for Ethanol Oxidation Reaction

Fabrication of novel noble-metal-free ZnIn2S4/WC Schottky junction heterojunction photocatalyst: efficient charge separation, increased active sites and low hydrogen production overpotential for boosting visible-light H2 evolution

Formic acid (FA), a major product formed in biomass processing and CO2 reduction, has attracted considerable attention as a promising renewable liquid-phase hydrogen carrier. Designing highly efficient catalysts for FA dehydrogenation is a key challenge for fuel cell-based hydrogen economy. Herein, Pd-WOx nano-heterostructures (2.9 nm in diameter) anchored on ZIF-8 @ZIF-67 core-hell MOFs-derived nitrogen-doped porous carbon cage (NPCC) are fabricated for the first time through a phosphate mediation approach. Strong adsorption and dispersion of Pd2+ in the phosphate-modified NPCC are essential for the synthesis of highly dispersed ultrafine Pd nanoparticles. The alkaline solution produced during the subsequent reduction process of metal ions can remove the phosphate. The obtained Pd-WOx/(P)NPCC catalyst presents an extraordinarily catalytic performance (TOF, 2877 h–1 at 303 K and 6135 h–1 at 323 K) with a 100% H2 selectivity and conversion toward FA dehydrogenation. The superior performance of Pd–WOx/(P)NPCC is likely due to the strong interaction effect between Pd-WOx and NPCC; unique structures of Pd-WOx nano-heterostructures; and NPCC with hollow and large surface area and abundant surface defects. Kinetic isotope effect (KIE) measurements demonstrated that cleavage of CH bond is the rate-determining step for HCOOH dehydrogenation. This study provides new insights into a facile and controllable synthesis strategy of inexpensive and efficient catalysts for high-efficiency dehydrogenation of liquid-phase hydrogen carrier. 

Pd–WO heterostructures immobilized by MOFs-derived carbon cage for formic acid dehydrogenation

Magnetically recyclable ZnCo2O4/Co3O4 nano-photocatalyst: Green combustion preparation, characterization and its application for enhanced degradation of contaminated water under sunlight

Xiao Lan

Papers

Building P-doped MoS2/g-C3N4 layered heterojunction with a dual-internal electric field for efficient photocatalytic sterilization