Oxygen evolution nano

Doping conventional materials with a second element is an exciting strategy for enhancing catalytic performance via electronic structure modifications. Herein, Mn-doped CdS thin films were successfully synthesized with the aid of the chemical bath deposition (CBD) by varying the pH value (8, 10, and 12) and the surfactant amount (20, 40, 60 mg). Different morphologies like nano-cubes, nanoflakes, nano-worms, and nanosheets were obtained under different deposition conditions. The optimized Mn-doped CdS synthesized at pH=8 exhibited better photoelectrochemical (PEC) performance for oxygen evolution reaction (OER) than pure CdS films, with a maximum photocurrent density of 300 µA/cm2 at an external potential of 0...

Dual-atom catalytic sites on conductive substrates offer a promising opportunity for accelerating the kinetics of multistep hydrogen and oxygen evolution reactions (HER and OER, respectively). Using MXenes as substrates is a promising strategy for depositing those dual-atom electrocatalysts, if the efficient surface anchoring strategy ensuring metal-substrate interactions and sufficient mass loading is established. We introduce a surface-modification strategy of MXene substrates by preadsorbing L-tryptophan molecules, which enabled attachment of dual-atom Co/Ni electrocatalyst at the surface of Ti3 C2 T x by forming N-Co/Ni-O bonds, with mass loading reaching as high as 5...

Developing high-active and inexpensive electrocatalysts for oxygen evolution reaction (OER) is very important in the field of water splitting. The catalytic performance of electrocatalysts can be significantly improved by optimizing the electronic structure and designing suitable nanostructure. In this work, we represent the synthesis of hollow CoVOx /Ag-5 for OER. Due to the interaction of CoVOx and Ag nanoparticles, the electronic structure is optimized to improve the intrinsic catalytic activity. Additionally, the extrinsic catalytic activity of CoVOx /Ag is enhanced by the abundant active sites from the hollow structure...

Elevations in antibiotic resistance genes (ARGs) are due not only to the antibiotic burden, but also to numerous environmental pressures (e.g., pesticides, metal ions, or psychotropic pharmaceuticals), which have led to an international public health emergency. Metal-based nanoparticles (MNPs) poison bacteria while propelling nanoresistance at ambient or sub-lethal concentrations, acting as a wide spectrum germicidal agent. Awareness of MNPs driven antibiotic resistance has created a surge of investigation into the molecule mechanisms of evolving and spreading environmental antibiotic resistome...

Constructing the efficacious and applicable bi-functional electrocatalysts and establishing out the mechanisms of organic electro-oxidation by replacing anodic oxygen evolution reaction (OER) are critical to the development of electrochemically-driven technologies for efficient hydrogen production and avoid CO2 emission. Herein, the hetero-nanocrystals between monodispersed Pt (~ 2 nm) and Ni3 S2 (~ 9.6 nm) are constructed as active electrocatalysts through interfacial electronic modulation, which exhibit superior bi-functional activities for methanol selective oxidation and H2 generation...

Alkaline water electrolysis is promising for low-cost and scalable hydrogen production. Renewable energy-driven alkaline water electrolysis requires highly effective electrocatalysts for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). However, the most active electrocatalysts show orders of magnitude lower performance in alkaline electrolytes than that in acidic ones. To improve such catalysts, heterojunction engineering has been exploited as the most efficient strategy to overcome the activity limitations of the single component in the catalyst...

Layered Li-rich oxide cathode materials are capable of offering high energy density due to their cumulative cationic and anionic redox mechanism during (de)lithiation process. However, the structural instability of the layered Li-rich oxide cathode materials, especially in the deeply delitiated state, results in severe capacity and voltage degradation. Considering the minimal isotropic structural evolution of disordered rock salt oxide cathode during cycling, cation-disordered nano-domains have been controllably introduced into layered Li-rich oxides by co-doping of d0 -TM and alkali ions...

Single-atom catalysts, known for their high activity, have garnered significant interest. Currently, single-atom catalysts were prepared mainly on 2D substrates with random distribution. Here, we report a strategy for preparing arrayed single Pt (Pt1 ) atoms, which are templated through coordination with phosphotungstic acids (PTA) intercalated inside hexagonally packed silicate nanochannels for a high single Pt-atom loading of ca. 3.0 wt %. X-ray absorption spectroscopy, high-angle annular dark-field scanning transmission electron microscopy, and energy-dispersive X-ray spectroscopy, in conjunction with the density-functional theory calculation, collectively indicate that the Pt single atoms are stabilized via a four-oxygen coordination on the PTA within the nanochannels' inner walls...

The development of catalysts for an economical and efficient oxygen evolution reaction (OER) is critical for clean and sustainable energy storage and conversion. Nickel-iron-based (NiFe) nanostructures are widely investigated as active OER catalysts and especially shape-controlled nanocrystals exhibit optimized surface structure and electronic properties. However, the structural control from amorphous to well-defined crystals is usually time-consuming and requires multiple stages. Here, a universal two-step precipitation-hydrothermal approach is reported to prepare a series of NiFe-based nanocrystals (e...

By substituting the oxygen evolution reaction (OER) with the anodic urea oxidation reaction (UOR), it not only reduces energy consumption for green hydrogen generation but also allows purification of urea-rich wastewater. Spin engineering of the d orbital and oxygen-containing adsorbates has been recognized as an effective pathway for enhancing the performance of electrocatalysts. In this work, we report the fabrication of a bifunctional electrocatalyst composed of amorphous RuO2 -coated NiO ultrathin nanosheets (a-RuO2 /NiO) with abundant amorphous/crystalline interfaces for hydrogen evolution reaction (HER) and UOR...

The development of cost-effective catalysts for oxygen evolution reaction (OER) in acidic media is of paramount importance. This work reports that Sr-doped solid solution structure ultrafine IrMnO2 nanoparticles (∼1.56 nm) on the CNTs (Sr-IrMnO2 /CNTs) are efficient catalysts for the acidic OER. Even with the Ir use dosage 3.5 times lower than that of the commercial IrO2 , the Sr-IrMnO2 /CNTs only needs an overpotential of 236.0 mV to drive 10.0 mA cm-2 and shows outstanding stability for > 400...

Transition metal-based catalysts possess high catalytic activity for oxygen evolution reaction (OER). However, the preparation of high-performance OER electrocatalysts using simple strategies with a low cost still faces a major challenge. Herein, this work presents an innovative, in situ-induced preparation of the Fe2 O3 , FeS, and NiS nanoparticles, supported on carbon blacks (CBs) (denoted as Fe2 O3 -Fe(Ni)S/C) as a high-efficiency oxygen evolution electrocatalyst by employing biomineralization. Biomineralization, a simple synthesis strategy, demonstrates a huge advantage in controlling the size of the Fe2 O3 and Fe(Ni)S nanoparticles, as well as achieving uniform nanoparticle distribution on carbon blacks...

Enzyme-mimicking confined catalysis has attracted great interest in heterogeneous catalytic systems that can regulate the geometric or electronic structure of the active site and improve its performance. Herein, a liquid-assisted chemical vapor deposition (LCVD) strategy is proposed to simultaneously confine the single-atom Ru sites onto sidewalls and Janus Ni/NiO nanoparticles (NPs) at the apical nanocavities to thoroughly energize the N-doped carbon nanotube arrays (denoted as Ni/NiO@Ru-NC). The bifunctional Ni/NiO@Ru-NC electrocatalyst exhibits overpotentials of 88 and 261 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at 100 mA cm-2 in alkaline solution, respectively, all ranking the top tier among the carbon-supported metal-based electrocatalysts...

The strategic field of renewable energy production and storage requires novel nanoscale platforms that can feature competitive solar energy conversion properties. Photochemical reactions that promote energy storage, such as water splitting and oxygen-hydrogen evolution reactions, play a crucial role in this context. Here, we demonstrate a novel photoelectrochemical device based on large-area (cm2 ) self-organized Au nanowire (NW) arrays, uniformly coated with ultrathin TiO2 films. The NW arrays act both as transparent nanoelectrodes and as a plasmonic metasurface that resonantly enhances the very weak visible photocurrent generated by a prototype photoelectrochemical oxygen evolution reaction...

The exploitation of efficient, stable and cheap electrocatalyst for oxygen evolution reaction (OER) is very significant to the development of energy technology. In this study, Fe-based metal-organic frameworks (MIL-53(Fe)) self-supporting electrode with a 3D hierarchical open structure was developed through a semi-sacrificial strategy. The self-supporting electrode exhibits an excellent OER performance with an overpotential of 328 mV at 100 mA cm-2 in 1 M KOH, which is superior than that of IrO2 catalyst...

Developing low-cost and self-supported bifunctional catalysts for highly efficient water splitting devices is of great significance. Herein, different from previously reported NiFe2 O4 -based electrocatalysts, we have grown nano-NiFe2 O4 directly onto the iron foil (IF) surface and in situ introduced Sn4+ into NiFe2 O4 . The resulting experimental phenomena confirmed that the as-synthesized Sn-NiFe2 O4 /IF can deliver large-current densities (>1000 mA cm-2 ) during oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) processes at a low overpotential...

The development of highly active and stable electrode materials for the oxygen evolution reaction (OER) is essential for the widespread application of electrochemical energy conversion systems. In recent years, various metal-organic frameworks (MOFs) with self-supporting array structures have been extensively studied because of their high porosity, abundant metal sites, and flexible and adjustable structures. This review provides an overview of the recent progress in the design, preparation, and applications of MOF-based nanoarrays for the OER, beginning with the introduction of the architectural advantages of the nanoarrays and the characteristics of MOFs...

In the pursuit of efficient solar-driven electrocatalytic water splitting for hydrogen production, the intrinsic challenges posed by the sluggish kinetics of anodic oxygen evolution and intermittent sunlight have prompted the need for innovative energy systems. Here, we introduce an approach by coupling the polysulfides oxidation reaction with the hydrogen evolution reaction for energy-saving H2 production, which could be powered by an aqueous zinc-polysulfides battery to construct a self-powered energy system...

The formation of multiple oxygen intermediates supporting efficient oxygen evolution reaction (OER) are affinitive with hydroxyl adsorption. However, ability of the catalyst to capture hydroxyl and maintain the continuous supply at active sits remains a tremendous challenge. Herein, an affordable Ni2 P/FeP2 heterostructure is presented to form the internal polarization field (IPF), arising hydroxyl spillover (HOSo) during OER. Facilitated by IPF, the oriented HOSo from FeP2 to Ni2 P can activate the Ni site with a new hydroxyl transmission channel and build the optimized reaction path of oxygen intermediates for lower adsorption energy, boosting the OER activity (242 mV vs...

Solar-driven water splitting powered by photovoltaics enables efficient storage of solar energy in the form of hydrogen fuel. In this work, we demonstrate efficient solar-to-hydrogen conversion using perovskite (PVK) tandem photovoltaics and a halogen-modulated metal-organic framework (MOF) electrocatalyst. By substituting tetrafluoroterephthalate (TFBDC) for terephthalic (BDC) ligands in a nickel-based MOF, we achieve a 152 mV improvement in oxygen evolution reaction (OER) overpotential at 10 mA·cm2 ...