Importing Antibonding‐Orbital Occupancy through Pd−O−Gd Bridge Promotes Electrocatalytic Oxygen Reduction

Abstract

The active‐site density, intrinsic activity, and durability of Pd‐based materials for oxygen reduction reaction (ORR) are critical to their application in industrial energy devices. This work constructs a series of carbon‐based rare‐earth (RE) oxides (Gd2O3, Sm2O3, Eu2O3, and CeO2) by using RE metal‐organic frameworks to tune the ORR performance of the Pd sites through the Pd‐RExOy interface interaction. Taking Pd‐Gd2O3/C as a representative, it is identified that the strong coupling between Pd and Gd2O3 induces the formation of the Pd‐O‐Gd bridge, which triggers charge redistribution of Pd and Gd2O3. The screened Pd‐Gd2O3/C exhibits impressive ORR performance with high onset potential (0.986 VRHE), half‐wave potential (0.877 VRHE), and excellent stability. Similar ORR results are also found for Pd‐Sm2O3/C, Pd‐Eu2O3/C, and Pd‐CeO2/C catalysts. Theoretical analyses reveal that the coupling between Pd and Gd2O3 promotes electron transfer through the Pd‐O‐Gd bridge, which induces the antibonding‐orbital occupancy of Pd‐*OH for the optimization of *OH adsorption in the rate‐determining step of ORR. The pH‐dependent microkinetic modeling shows that Pd‐Gd2O3 is close to the theoretical optimal activity for ORR, outperforming Pt under the same conditions. By its ascendancy in ORR, the Pd‐Gd2O3/C exhibits superior performance in Zn‐air battery as an air cathode, implying its excellent practicability.

Potential-Resolved Ratiometric Aptasensor for Sensitive Acetamiprid Analysis Based on Coreactant-free Electrochemiluminescence Luminophores of Gd-MOF and “Light Switch” Molecule of [Ru(bpy)2dppz]2+

“…33,34 For the highresolution spectrum of Gd 4d (Figure 1i), the two fitted peaks with the binding energy of 142.7 and 148.0 eV can be ascribed to Gd 4d 5/2 and Gd 4d 3/2 , further verifying the presence of Gd 3+ . 35,36 The C 1s spectrum (Figure S1b) can be divided into three characteristic peaks located at 284.2, 288.1, and 289.5 eV, which are severally attributed to the C�C, C−O, and C�O bonds. 37 Additionally, the two splitting peaks at 531.0 and 531.9 eV for the O 1s spectrum (Figure S1c) are associated with the C�O and Gd−O bonds, respectively.…”

Co, Fe decorated N, S co-doped porous carbon enables high stability for the oxygen reduction reaction

“…These issues need to be solved urgently, including the preparation of high efficiency oxygen electrocatalysts. 11,12 Typically, M–N–C materials, possessing comparable stable active sites and excellent activity, are promising for the ORR. 13–16 Generally, these materials are obtained by pyrolyzing the metal and carbon precursors, and their ORR performance is closely related to the precursor's structure.…”

MOF-Derived Cobalt Nanoparticles with Dispersed Iron Phthalocyanines as Bifunctional Oxygen Electrocatalysts

“…Currently, metal–organic framework (MOF) materials have emerged as one subclass of crystalline and microporous solids, characterized by their structural assembly from organic linkers and metal ions. − Through suitable thermal and/or chemical processes, these hybrid MOFs can be effectively transformed into diverse high-energy storage materials, − including porous carbon, , metal hydroxides, , oxides, , carbides, , and nitrides. − In this category, derivatives of zeolitic imidazolate framework (ZIF) exhibit intrinsic properties of high graphitization and enhanced charge transport capabilities. , Meanwhile, microporous MOF materials can also act as templates for the facile synthesis of multifunctional carbon materials, which are structurally endowed with a large pore volume and tunable morphology . MOF-derived carbons show abundant pores that facilitate reaction intermediates as well as electrolytes during electrocatalysis .…”

“…14−19 Currently, metal−organic framework (MOF) materials have emerged as one subclass of crystalline and microporous solids, characterized by their structural assembly from organic linkers and metal ions. 20−23 Through suitable thermal and/or chemical processes, these hybrid MOFs can be effectively transformed into diverse high-energy storage materials, 24−26 including porous carbon, 27,28 metal hydroxides, 29,30 oxides, 31,32 carbides, 33,34 and nitrides. 35−37 In this category, derivatives of zeolitic imidazolate framework (ZIF) exhibit intrinsic properties of high graphitization and enhanced charge transport capabilities.…”