Constructed Interfacial Oxygen‐Bridge Chemical Bonding in Core‐Shell Transition Metal Phosphides/Carbon Hybrid Boosting Oxygen Evolution Reaction

Abstract

A designed structure which CoP nanoparticles (NPs) ingeniously connected with graphene-like carbon layer via in-situ generated interfacial oxygen-bridge chemical bonding was achieved by a mild phosphorization treatment. The results proved that the presence of phosphorus vacancies is a crucial factor enabling formation of CoÀ OÀ C bonds. The direct coupling of edge Co of CoP with the oxygen from functional groups on the carbon layer was proposed. As a catalyst for electrocatalytic water splitting, the manufactured Fe 2 O 3 @C@CoP core-shell structure manifested a low overpotential of 230 mV, a low Tafel slope of 55 mV dec À 1 , and long-term stability. Density functional theory calculations verified that the CoÀ OÀ C bond played a critical role in decreasing the thermodynamic energy barrier of reaction rate-determining step for the oxygen evolution reaction (OER). This synthetic route might be extended to construct metalÀ OÀ C bonds in other transition metal phosphides (or selenides, sulfides)/carbon composites for highly efficient OER catalysts.

Single-Atom and Bimetallic Nanoalloy Supported on Nanotubes as a Bifunctional Electrocatalyst for Ultrahigh-Current-Density Overall Water Splitting

“…Similarly, due to the peeling of CNT during argon etching, the peak of CO becomes less obvious. The chemical bond of M–O–C, detected in both C 1s and O 1s spectra, can accelerate the electron transfer and improve the catalytic kinetic speed according to previous reports …”

Stabilization of ruthenium nanoparticles over NiV-LDH surface for enhanced electrochemical water splitting: an oxygen vacancy approach

“…Many reports exhibited that various derivatives of 1 st -row transition metal-based catalysts like sulphides, phosphides, selenides, hydroxides and oxides are reported to be most effective for OER and HER. 18–29 Recently, some reports showed that transition metal-based LDHs are effective for both OER and HER because of their unique layered structure in various electrolyte medium. 18–29 So far, many bimetallic transition metal-based layered double hydroxide (LDH) materials such NiFe-LDH, CoFe-LDH, CoNi-LDH, CoMn-LDH, and NiV-LDH have been reported widely as catalysts for water splitting reaction.…”

“…18–29 Recently, some reports showed that transition metal-based LDHs are effective for both OER and HER because of their unique layered structure in various electrolyte medium. 18–29 So far, many bimetallic transition metal-based layered double hydroxide (LDH) materials such NiFe-LDH, CoFe-LDH, CoNi-LDH, CoMn-LDH, and NiV-LDH have been reported widely as catalysts for water splitting reaction. 30–40 Some of them showed excellent OER and HER activity in various pH conditions.…”

Graphene-based materials as electrocatalysts for the oxygen evolution reaction: a review

“…Recently, various transition-based metal oxides, hydroxides, LDHs, chalcogenides, phosphides and nitride-based materials have attracted much attention from researcher due to their fascinating electrocatalytic activity and unique stability, irrespective of the medium used as the electrolyte. 14–19 However, although numerous reports are available on these transition metal derivatives for the OER and HER with good stability, owing to their low conductivity, especially transition metal-based oxides, LDH, hydroxides and oxyhydroxides, their application towards the large-scale production of hydrogen still a challenge. 4 Thus, to overcome this issue, researchers focused on the modification of the above-mentioned materials by adopting various strategies such as the incorporation of foreign cations or anions, creation of vacancies and enhancing the conductivity of electrocatalyst materials by using various conductive supports such as nickel foam (NF), copper foam (CF) and graphene-based materials.…”

“…4 Thus, to overcome this issue, researchers focused on the modification of the above-mentioned materials by adopting various strategies such as the incorporation of foreign cations or anions, creation of vacancies and enhancing the conductivity of electrocatalyst materials by using various conductive supports such as nickel foam (NF), copper foam (CF) and graphene-based materials. 19–23 Among them, the use of graphene-based composites with transition metal-based derivatives has attracted significant attention not only for the fabrication of excellent water splitting electrocatalysts but also materials for other electrochemical applications such as batteries, sensors, and supercapacitor applications. 24–29 Graphene with a conjugated hexagonal lattice and fascinating two-dimensional nanosheet-like structure, has attracted significant attention for the preparation of energy storage and conversion devices owing to its huge surface to volume ratio, great electrical conductivity and high electrochemical stability.…”