ABSTRACT
The addition of an extra metal source induces the transformation from crystalline α-Ni(OH)2 to an amorphous NiCoFeCrMo-based high-entropy hydroxide (HEH) and maximizes the high-valence Ni3+ content in HEH. For OER electrocatalysis, the quinary HEH possesses an overpotential of 292 mV at 10 mA cm-2, a Tafel slope of 54.31 mV dec-1 and the boosted intrinsic activity, surpassing other subsystems.
ABSTRACT
Herein, small Co nanoparticles (NPs) encapsulated in N-doped double-shelled carbon nanocages grafted with thin carbon nanotubes (Co@CNTs@DSCNCs) were synthesized from yolk-shell bimetallic zeolitic imidazolate framework (BMZIF). For HER electrocatalysis, they exhibit higher activity (η10 = 214 mV) and more favorable kinetics than Co@CNTs@PC (PC = porous carbon) with thick CNTs and large Co NPs derived from solid BMZIF cubes.
ABSTRACT
Herein, through a morphology-inherited annealing treatment of a hollow Fe-doped MOF-5 octahedron as the self-sacrificing template, we report the synthesis of concave ZnFe2O4 hollow octahedral nanocages as sensing materials, which exhibited high performance, including unprecedented excellent sensitivity, good selectivity, and cyclic stability at ultralow working temperature (120 °C).