Electrocatalytic Water Splitting Research Articles

A bimetallic NiFe MOF with ultra-thin two-dimensional nanosheet structure effectively accelerates oxygen evolution reaction.

To address the shortage of fossil energy, the development of affordable and efficient non-precious metal catalysts for oxygen evolution reaction (OER) from electrocatalytic water splitting is still a crucial challenge. Herein, the bimetallic NiFe metal-organic frameworks (MOFs) are synthesized by hydrothermal and electro-deposition. Benefiting from the synergistic effect of Fe and Ni, the catalyst demonstrates extraordinary activity, which exhibits favorable OER catalytic activity in 1 M KOH solution with an overpotential of 206 mV at 10 mA cm-2. Meanwhile, the obtained NiFe-NDC presents promising stability in the 20 h test at 50 mA cm-2.

Ag–NiP deposited green carbon channel embedded NiP panels for sustainable water splitting

Ag–NiP-deposited carbon channels on NiP panels were successfully developed through lemon juice extract (Ag–CL/NiP) and citric acid (Ag–CC/NiP)-assisted methodologies for photo and electrocatalytic water splitting.

Ruthenium-based single atom catalysts: synthesis and application in the electrocatalytic hydrogen evolution reaction.

Electrocatalytic water splitting is a promising production method for green hydrogen; however, its practical application is limited by the lack of robust catalysts for the cathode hydrogen evolution reaction (HER). Recently, the use of Ru in electrocatalytic HER has become a research hotspot because Ru has a metal-hydrogen bond strength similar to that of Pt - known for its excellent HER activity - but has a lower cost than Pt. Numerous modification strategies are available to further improve the HER activity of metal Ru such as vulcanisation, phosphating and atomisation. The atomisation strategy has attracted much attention owing to its extremely high Ru atomic utilisation efficiency and tunable electronic structures. However, isolated studies could not effectively address the bottlenecks. Therefore, to promote the effective exploration of Ru-based single-atom catalysts and clarify the research status in this field, studies on related topics (e.g. Ru single-atom catalysts, Ru dual-atom catalysts, composite catalysts containing single-atom Ru and Ru nanoparticles) have been systematically and briefly summarised herein. Finally, the research challenges and prospects of Ru-based single-atom catalysts in the HER field have been discussed, which may provide valuable insights for further research.

Hierarchical FeCo LDH/NiSe heterostructure electrocatalysts with rich heterointerfaces for robust water splitting at industrial-level current density

Sustainable hydrogen production by electrocatalytic water splitting is a promising energy storage technology yet challenging due to the sluggish kinetics of the oxygen evolution reaction (OER). Rationally designed robust and...

Ruthenium clusters decorating on lattice expanded hematite Fe2O3 for efficient electrocatalytic alkaline water splitting

Electrocatalytic water splitting in alkaline media plays an important role in hydrogen production technology. Normally, the catalytic activity of commonly used transition metal oxides usually suffers from unsatisfactory electron conductivity...

Metal-organic framework-derived Se-blended ZrO2 with a nitrogen-doped carbon heterostructure for electrocatalytic overall water splitting.

Designing low cost, highly active and efficient non-noble metal bifunctional electrocatalysts with remarkable operational reliability for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is indispensable for large-scale water electrolysis and the development of clean energy conversion technologies. Herein, we decorated a two-dimensional (2D) selenium-blended zirconium dioxide (Se-ZrO2) on the surface of a nitrogen-doped carbon heterostructure (Se-ZrO2@NC), which was derived from Zr-metal-organic frameworks (Zr-MOFs), and loaded it on a stainless-steel mesh electrode. Accordingly, phenomenal electrocatalytic performance was observed for the Se-ZrO2@NC-loaded electrode with a minimum overpotential of 48 mV for the HER and 251 mV for the OER at 10 mA cm-2 current density in acidic and alkaline mediums, respectively. Moreover, a complete cell set up was constructed, where the OER and HER were studied at the anode and cathode, respectively, with a cell potential of 1.58 V to reach a current density of 10 mA cm-2 together with an exciting long-term stability of over 48 h. The developed Se-blended 2D transition metal dioxides on the 2D nitrogen-doped carbon heterostructure extended to a variety of catalytically active materials that would provide highly active and stable electrocatalysts for alkaline water splitting studies.

Enhanced electrocatalytic overall alkaline water splitting induced by interfacial electron coupling of Mn3O4 nano-cube@CeO2/γ-FeOOH nanosheet hetero-structure

Mn3O4@CeO2/γ-FeOOH hetero-structure showed interfacial electron coupling induced superior bifunctional electrocatalytic activity suitable for AEM electrolyser.

Phytic acid treated nickel–iron hydroxide promotes efficient electrocatalytic overall water splitting

Phytic acid-treated NiFe-LDH exposes more active sites and can improve the electrocatalytic performance in water splitting.

Water electrolysis for hydrogen production: from hybrid systems to self-powered/catalyzed devices

This perspective highlights recent advancements in innovative strategies to provide valuable insights into the potential for energy-saving hydrogen production through water electrolysis.

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

The electrocatalytic splitting of water to produce hydrogen is regarded as an efficient and promising strategy but is limited by its large overpotential; thus, a highly efficient electrocatalyst is urgently needed. Mixed metal doping is an important strategy in defect engineering because the heteroatoms can change the intrinsic structure to form defects by affecting the atomic coordination mode and adjusting the electronic structure, which is often accompanied by morphological changes. Herein, two-dimensional layered bimetallic Co-pydc containing axially coordinated water molecules was selected by producing surface defects through Fe doping in Co centers as bifunctional electrocatalysts for OER and HER. The optimized Co0.59Fe0.41-pydc possesses outstanding OER performance with the lowest overpotential of 262 mV to reach j = 10 mA cm-2, and Co0.75Fe0.25-pydc possesses superior HER performance with the lowest overpotential of 96 mV at j = 10 mA cm-2. Furthermore, the overall water splitting device assembled with Co0.59Fe0.41-pydc@NF//Co0.59Fe0.41-pydc@NF affords a current density of 10 mA cm-2 at only 1.687 V. This work emphasizes the surface defects formed by tuning the electronic structure of metal centres accompanied with morphological changes of bimetallic dopants for efficient overall water splitting.

Non-noble metal coordinated hypercrosslinked polymers based on porphyrin for efficient electrocatalytic OER

Electrochemical catalysts for the oxygen evolution reaction (OER) with abundant reserves, high catalytic activity, and robust stability are highly crucial for efficient electrocatalytic water splitting.

Rational design of local microenvironment for electrocatalytic water splitting

This summary describes the effects of wettability, local pH, interfacial water structure, and electrolyte composition on the interface reactant compositions, key intermediate adsorption, and reaction kinetics.

Modulating the electronic structure of Ru using a self-reconstructed MOF-NiFeOOH heterointerface for improved electrocatalytic water splitting

The Ru-doped and self-supported metal–organic framework/NiFe foam electrode demonstrates an efficient and durable electrocatalytic activity for overall water splitting.

Engineering 2D nickel boride/borate amorphous/amorphous heterostructures for electrocatalytic water splitting and magnetism

Engineering nickel boride/borate amorphous/amorphous heterostructures using a simple one-pot chemical reduction method.

Ohmic contact interface in the self-surface reconstructed Ni4Mo/MoO2 heterostructure for achieving effective alkaline electrocatalytic water splitting

We developed Ni4Mo/MoO2, a metal/n-type semiconductor junction forming ohmic contact in p–n junction for both OER and HER due to conversion of Ni4Mo into NiOOH and Ni(OH)2, respectively.

A bifunctional electrocatalyst based on interfacial engineering of CeO2 and NiSe2 for boosting electrocatalytic water splitting

A novel bifunctional electrocatalyst with a 3D structural CeO2–NiSe2 in situ grown on nickel foam is reported. It shows remarkable activities for the OER and the HER as well as superior electrocatalyst performance in overall water splitting.

Two dimensional oxides for oxygen evolution reactions and related device applications

The oxygen evolution reaction (OER) is a key anode reaction for many renewable energy devices, such as electrocatalytic water splitting devices, Zn–air batteries and CO2 electrolyzers.

Regulating catalytic kinetics in nanoclimbing-wall-like NiO/NiCoP hybrids for enhanced overall water splitting

Developing integrated cost-efficient bifunctional electrocatalysts with unique architecture comparable to noble metal is greatly desirable for efficient electrocatalytic water splitting. Herein, a highly active NiO/NiCoP hybrid catalyst on nickel foam...

Design of nanostructured 2D (photo-)electrocatalysts for biomass valorization coupled with H2 production

Electrocatalytic water splitting driven by renewable energy is a promising strategy for sustainable hydrogen production. However, the slow oxygen evolution reaction (OER) kinetics severely limit the rate of the hydrogen...

Integrated MXene and metal oxide electrocatalysts for the oxygen evolution reaction: synthesis, mechanisms, and advances.

Electrochemical water splitting is a promising approach to produce H2 through renewable electricity, but its energy efficiency is severely constrained by the kinetically slow anodic oxygen evolution reaction (OER), which uses about 90% of the electricity in the water-splitting process due to its multistep proton (H+)-coupled electron (e-) transfer process, high overpotential (η), and low energy efficiency. Therefore, the quest for efficient, sustainable, and cost-effective electrocatalysts for hydrogen production through water electrolysis has intensified, highlighting the potential of two-dimensional (2D) MXenes. MXenes have emerged as a promising class of materials characterized by excellent stability, hydrophilicity, and conductivity. However, challenges such as low oxidation resistance, facile stacking, and the absence of intrinsic catalytically active sites limit their performance. This review thoroughly explores various synthesis methods for MXenes and their integration with transition metal oxides (TMOs) to tackle the challenges and enhance catalytic activity. The review also delves into advanced strategies for structural tuning of MXenes and TMOs, such as termination engineering, heteroatom doping, defect engineering, and the formation of heterojunctions. The integration of MXenes with TMOs has addressed the current limitations of MXenes and significantly boosted OER activity. By considering these structural tuning parameters and limitation factors, researchers can gain insights into the design principles and optimization strategies for MXene- and TMO-integrated electrocatalysts. The review concludes with a summary of the key findings and an outlook on future research directions, emphasizing the unexplored potential and innovative approaches that could further advance the field of electrocatalytic water splitting.