Self-Supportive Bimetallic Selenide Heteronanostructures as High-Efficiency Electro(pre)catalysts for Water Oxidation

Abstract

Developing oxygen evolution reaction (OER) catalysts is intricate and challenging, involving a four-electron transport process coupled with conversion of O−H bonds into O− O bonds. This paper proposes a simple one-step synthetic strategy for preparing self-supported Cu 2 Se/NiSe 2 heteronanostructure electrodes for the OER with well-defined heterointerfaces by directly embedding onto the conductive nickel foam substrate. The prepared catalyst significantly enhances OER activity with low overpotentials of 277 and 290 mV at current densities of 50 and 100 mA cm −2 , respectively, which is attributed to electronic structure modulation by synergetic interactions and enhanced charge transportation between Cu 2 Se and NiSe 2 nanostructures. The as-prepared electrodes achieved high durability in 1 M KOH, retaining initial activity levels after 24 h continuous operation. We performed comprehensive spectroscopic and microscopic characterization before and after the OER to clarify active species and relate them to OER catalysis. Enhanced catalyst efficiency arises from integrating multicomponent electrocatalytic systems, which has been emphasized by the present findings.

Metal–Organic Framework-Derived Fe-Doped CoF2/NF Composite as Bifunctional Electrocatalyst for Oxygen Evolution and Hydrazine Oxidation

“…Accordingly, the spectrum of F 1s (Figure d) shows that the Co–F bond completely disappeared, indicating that F dissolves in the electrolyte in the OER process, which is beneficial to surface reconstruction. , Simultaneously, in the XPS spectrum of O 1s (Figure S13), peaks of 529.06 and 531.0 eV are allocated to metal oxide and lattice oxygen, and the peak at 532.75 eV belongs to H 2 O, implying the formation of CoOOH. These results indicate the occurrence of surface reconstruction and the formation of active intermediate of CoOOH on the surface of Fe–CoF 2 /NF during the OER, which is the real active sites of OER. , …”

“…These results indicate the occurrence of surface reconstruction and the formation of active intermediate of CoOOH on the surface of Fe−CoF 2 /NF during the OER, which is the real active sites of OER. 35,54 On the basis of these results, a possible mechanism of the OER in alkaline electrolytes is discussed as follows: 4…”

Low-Potential Overall Water Splitting Induced by Engineered CoTe2–WTe2 Heterointerfaces

“…Feng’s group showed that Fe-doped CoTe results in a robust electrocatalyst for OER with η = 300 mV ( j = 0.01 A cm –2 ) . Rational design of nanostructures via heterointerface engineering with diverse materials results in a favorable electronic structure and increased active sites for reaction, which boosts the electrocatalytic activity of both HER and OER by addressing the issues of pure CoTe 2 . , In this context, tungsten telluride (WTe 2 ), a layered semimetal telluride and a proven electrocatalyst for HER, is of interest. − Wu et al used a hydrothermal technique to create a phosphorus-doped WTe 2 core covered with an amorphous phosphate shell which exhibited η = 220 mV ( j = 0.01 A cm –2 ) in acidic medium and η = 280 mV ( j = 0.01 A cm –2 ) in alkaline medium, respectively, for OER. Surface coating increased the abundance of active sites, while the doped crystalline core facilitated electron transport to the active sites, leading to good performance .…”

“…30 heterointerface engineering with diverse materials results in a favorable electronic structure and increased active sites for reaction, which boosts the electrocatalytic activity of both HER and OER by addressing the issues of pure CoTe 2 . 31,32 In this context, tungsten telluride (WTe 2 ), a layered semimetal telluride and a proven electrocatalyst for HER, is of interest. 33−36 Wu et al used a hydrothermal technique to create a phosphorus-doped WTe 2 core covered with an amorphous phosphate shell which exhibited η = 220 mV (j = 0.01 A cm −2 ) in acidic medium and η = 280 mV (j = 0.01 A cm −2 ) in alkaline medium, respectively, for OER.…”

Rational Design and Engineering of Metal–Organic Framework-Derived Trimetallic NiCoFe-Layered Double Hydroxides as Efficient Electrocatalysts for Water Oxidation Reaction

“…With the growing worldwide demand for energy necessities and environmental protection, the progress of renewable energy production has motivated several research investigations. − The advancement of green renewable energy production plays a significant role in addressing major environmental and energy crises, including fossil fuel depletion and global warming caused by the combustion of fossil fuels rapidly emitting CO 2 . − Nevertheless, the renewable energy sources that produce clean electricity including wind and solar energies are largely eroded by usual environmental conditions, which in turn leads to a lack of stability. Therefore, it is highly essential to develop methodologies that can effectively store energy and deliver a steady power supply whenever required.…”