Vanadium-Based Trimetallic Metal-Organic-Framework Family as Extremely High-Performing and Ultrastable Electrocatalysts for Water Splitting

Abstract

This is the first time that the pore-space-partition (PSP) strategy is being successfully applied in the electrochemical field for water splitting, realizing the highly efficient construction of a series of ultrastable pristine MOF electrocatalysts. On integrating the vanadiumbased trimetallic building cluster (M 2 V), the target M 2 V-MOFs exhibit excellent electrocatalytic activity for HER, OER, and water splitting. In particular, ultralow overpotentials of 314 and 198 mV for Fe 2 V-MOF as OER and HER electrocatalysts, respectively, can drive a current density of 10 mA cm −2 . The fabricated Fe 2 V-MOF||Pt/C two-electrode configuration for the overall water splitting yields a current density of 10 mA cm −2 at only 1.6 V vs RHE, which is superior to that of the commercial IrO 2 ||Pt/C couple. Notably, high structural and chemical stabilities still can be observed in alkaline condition. This work opens up an exciting pathway to design efficient and stable electrocatalysts based on pristine MOF by integrating the PSP strategy and multimetallic centers.

Pillared-MOF@NiV-LDH Composite as a Remarkable Electrocatalyst for Water Oxidation

“…Characteristics such as large surface area, high conductivity, rich electroactive sites, and stability are crucial for these materials when considering their potential application as electrocatalysts. − To date, the most common electrocatalysts for OER are based on inorganic Ru- and Ir-containing materials, , which are generally meager and expensive for large-scale exploration. To overcome this limitation, there is a trend for the development of OER electrocatalysts based on low-cost, earth-abundant, and electroactive metals such as Ni, Co, and V. − …”

NiFeCu phosphides with surface reconstruction via the topotactic transformation of layered double hydroxides for overall water splitting

“…In general, the OER pathway is a four-electron transfer step, including: * + H 2 O → *OH + (H + + e − ), *OH → *O + (H + + e − ), *O + H 2 O − → *OOH + (H + + e − ), and *OOH → * + O 2 + (H + + e − ). 37,38 The adsorption energies of oxygen-containing intermediates (OH*, O* and OOH*) on the catalysts at U = 0 V and 1.23 V are calculated to explain the mechanism of the excellent OER performance (Fig. 7a).…”

Surface defect-engineered Fe doping in layered Co-based complex as highly efficient bifunctional electrocatalysts for overall water splitting

“…2b) and could be attributed to Fe 2p 1/2 and Fe 2p 3/2 , respectively, suggesting the presence of Fe 2+ . 37 The peaks at 713.9 eV can be assigned to Fe 3+ , due to the spontaneous oxidation of Fe 2+ during the synthesis and measurements. The Fe 2p spectrum of Co 0.75 Fe 0.25 -pydc was similar to that of Co 0.59 Fe 0.41 -pydc (Fig.…”