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Engineering high‐performance and low‐cost bifunctional catalysts for H2 (hydrogen evolution reaction [HER]) and O2 (oxygen evolution reaction [OER]) evolution under industrial electrocatalytic conditions remains challenging. Here, for the first time, we use the stronger electronegativity of a rare‐Earth yttrium ion (Y3+) to induce in situ NiCo‐layered double‐hydroxide nanosheets from NiCo foam (NCF) treated by a dielectric barrier discharge plasma NCF (PNCF), and then obtain nitrogen‐doped YNiCo phosphide (N‐YNiCoP/PNCF) after the phosphating process using radiofrequency plasma in nitrogen. The obtained N‐YNiCoP/PNCF has a large specific surface area, rich heterointerfaces, and an optimized electronic structure, inducing high electrocatalytic activity in HER (331 mV vs. 2000 mA cm−2) and OER (464 mV vs. 2000 mA cm−2) reactions in 1 M KOH electrolyte. X‐ray absorption spectroscopy and density functional theory quantum chemistry calculations reveal that the coordination number of CoNi decreased with the incorporation of Y atoms, which induce much shorter bonds of Ni and Co ions and promote long‐term stability of N‐YNiCoP in HER and OER under the simulated industrial conditions. Meanwhile, the CoN‐YP5 heterointerface formed by plasma N‐doping is the active center for overall water splitting. This work expands the applications of rare‐Earth elements in engineering bifunctional electrocatalysts and provides a new avenue for designing high‐performance transition‐metal‐based catalysts in the renewable energy field. A N‐YNiCoP nanosheet structure is in situ engineered on Ni–Co foam using a dual‐plasma technique and acts as a bifunctional electrocatalyst for water splitting. The formed rich heterointerfaces and N‐doping effectively tune the electronic states of the catalyst, resulting in high hydrogen evolution reaction and oxygen evolution reaction performances in an alkaline medium at an industrial‐scale current density of 2000 mA cm−2.

PtRu/C (100% C) and PtRu/C-CeO2, PtRu/C-La2O3, PtRu/C-Nd2O3, and PtRu/C-Er2O3 (85% C and 15% rare earth) electrocatalysts were prepared in a single step by an alcohol-reduction process using H2PtCl6 6H2O and RuCl3 xH2O as metal sources, ethylene glycol as solvent and reducing agent, Vulcan XC72 and rare earth (RE) as support. The electrocatalysts were characterized by energy dispersive X-ray, X-ray diffraction, and transmission electron microscopy. The performance for ethanol oxidation was investigated by cyclic voltammetry and chronoamperommetry at room temperature, and studies on the direct ethanol fuel cell were carried at 100 °C. The Pt:Ru atomic ratios were similar to the nominal used in preparation, and the average particle sizes were in the range of 2.0–3.0 nm. All PtRu/C-RE electrocatalysts showed an increase of performance for ethanol oxidation at room temperature and also on a single direct ethanol fuel cell tests in relation to PtRu/C electrocatalyst at 100 °C.

Designing Pt-based electrocatalysts with high catalytic activity and CO tolerance is challenging but extremely desirable for alkaline hydrogen oxidation reaction. Herein we report the design of a series of single-atom lanthanide (La, Ce, Pr, Nd, and Lu)-embedded ultrasmall Pt nanoclusters for efficient alkaline hydrogen electro-oxidation catalysis based on vapor filling and spatially confined reduction/growth of metal species. Mechanism studies reveal that oxophilic single-atom lanthanide species in Pt nanoclusters can serve as the Lewis acid site for selective OH - adsorption and regulate the binding strength of intermediates on Pt sites, which promotes the kinetics of hydrogen oxidation and CO oxidation by accelerating the combination of OH − and *H/*CO in kinetics and thermodynamics, endowing the electrocatalyst with up to 14.3-times higher mass activity than commercial Pt/C and enhanced CO tolerance. This work may shed light on the design of metal nanocluster-based electrocatalysts for energy conversion. Exploring enhanced catalysts for alkaline hydrogen oxidation with high catalytic activity and CO tolerance is highly desired yet challenging. Here, the authors report single-atom lanthanide embedded Pt nanoclusters with high activities and durability.

Direct ethanol fuel cells (DEFCs) have drawn attention for their simplicity, rapid start-up, high power density and environmental friendliness. Despite these advantages, the widespread application of DEFCs faces challenges, primarily due to the inadequate performance of anode and cathode catalysts. Pd-based materials have shown exceptional catalytic activity for both the ethanol oxidation reaction (EOR) and the oxygen reduction reaction (ORR). Alloying noble metals with rare earth elements has emerged as an effective strategy to further enhance the catalytic activity by modulating the electronic structure. In this study, we synthesized a series of palladium-rare earth (Pd 3 RE) alloys supported on carbon to serve as bifunctional catalysts that efficiently promote both ORR and EOR. Compared to Pd/C, the Pd 3 Tb/C catalyst exhibits 3.1-fold and 1.8-fold enhancement in activity for ORR and EOR, respectively. The charge transfer in the Pd 3 Tb/C results in an electron-rich Pd component, thereby weakening the binding energy with oxygen species and facilitating the two reactions.

In recent years, there has been significant interest in electrospinning technology across diverse disciplines. Nanofibers produced via electrospinning demonstrate increased specific surface areas and greater porosity, serving as essential components with significant implications for a wide range of applications. This article presents a summary of the utilization of electrospinning in the areas of photocatalysis, electrocatalysis, and magnetic responsiveness. In the field of photocatalysis, the primary emphasis lies on strategies aimed at augmenting the photocatalytic efficiency of electrospun titanium dioxide (TiO 2 ) fibers. Three strategies are currently utilized to enhance the wide bandgap of titanium dioxide (TiO 2 ): doping with transition metal elements, non-metal elements, and rare earth elements. Moreover, the enhancement of photocatalytic activity in TiO 2 can be achieved through its combination with other oxides. Within the realm of electrocatalysis, there is a close relationship between water splitting and electrocatalysis. Water splitting is the procedure of breaking down water into hydrogen and oxygen, typically carried out through electrochemical means involving the use of electrocatalysts to facilitate the redox reaction of water. The employment of electrocatalysts serves to diminish the energy requirements of water splitting and enhance the reaction velocity, thereby facilitating the overall water splitting process. Electrospun electrocatalysts are classified into various categories including precious metal electrocatalysts, transition metal electrocatalysts, transition metal oxide electrocatalysts, carbon–metal composite electrocatalysts, and carbon-based non-metal electrocatalysts. Carbon-based electrocatalysts, specifically non-metal carbon-based electrocatalysts, are emerging as a prominent area of research. In the realm of magnetic fibers, electrospun fibers can be categorized into three groups: magnetic metal fibers, magnetic compound fibers, and magnetic composite fibers. The addition of carbon-based materials broadens the research possibilities of magnetic fibers. Additionally, certain magnetic fibers demonstrate notable photocatalytic capabilities, suggesting promising opportunities for integrating magnetic responsiveness with photocatalysis in the field of electrospinning. In summary, we underscore the considerable importance of electrospinning technology in the areas of photocatalysis, electrocatalysis, and magnetic responsiveness, emphasizing its continuous potential for further advancement.

HighlightsThe 2.27-nm-thick hybridized quasi-2D structure of La2O3 crystalline nanoparticles embedded in La2O3 amorphous nanosheets (La2O3@NP-NS) exhibited a low overpotential of 310 mV at 10 mA cm−2.The mass activity of La2O3@NP-NS reached as high as 6666.7 A g−1 at overpotential of 310 mV. Such a high mass activity was more than three orders of magnitude higher than that of benchmark IrO2 (4.4 A g−1) and RuO2 (2.05 A g−1) and five orders of magnitude higher than that of commercial La2O3 (0.048 A g−1).Electrochemical catalysts for oxygen evolution reaction are a critical component for many renewable energy applications. To improve their catalytic kinetics and mass activity are essential for sustainable industrial applications. Here, we report a rare-earth metal-based oxide electrocatalyst comprised of ultrathin amorphous La2O3 nanosheets hybridized with uniform La2O3 nanoparticles (La2O3@NP-NS). Significantly improved OER performance is observed from the nanosheets with a nanometer-scale thickness. The as-synthesized 2.27-nm La2O3@NP-NS exhibits excellent catalytic kinetics with an overpotential of 310 mV at 10 mA cm−2, a small Tafel slope of 43.1 mV dec−1, and electrochemical impedance of 38 Ω. More importantly, due to the ultrasmall thickness, its mass activity, and turnover frequency reach as high as 6666.7 A g−1 and 5.79 s−1, respectively, at an overpotential of 310 mV. Such a high mass activity is more than three orders of magnitude higher than benchmark OER electrocatalysts, such as IrO2 and RuO2. This work presents a sustainable approach toward the development of highly efficient electrocatalysts with largely reduced mass loading of precious elements.

Zinc-air batteries (ZABs) are potential energy storage and conversion devices, but the poor performances of bifunctional electrocatalysts at the cathode are becoming a bottleneck. Herein, we first chose the rare-earth metal cerium (Ce) as the source to synthesize the amorphous/crystal hybrid Ce/Ce 2 O 2 S-MS Mott-Schottky heterojunction. Among the Ce/Ce 2 O 2 S-MS series, the Ce/Ce 2 O 2 S 1-x -MS shows the best bifunctional electrocatalytic performances with the half-wave potential of 0.76 V for ORR and OER potential of 1.59 V at 10 mA cm −2 , and the Δ E value is 0.83 V. The special 4f structure of Ce combined with the Mott-Schottky heterojunction provides full active sites and promotes electron transfer at the interface of heterojunction. Our study provides a potential conception for Ce-based bifunctional electrocatalysts applied in the ZABs.

With unique 4f electronic shells, rare earth metal-based catalysts have been attracting tremendous attention in electrocatalysis, including oxygen reduction reaction (ORR). In particular, atomically dispersed Ce/CeO2-based catalysts have been explored extensively due to several unique features. This review article provides a comprehensive understanding of (i) the significance of the effect of Ce high-spin state on ORR activity enhancement on the Pt and non-pt electrocatalysts, (ii) the spatially confining and stabilizing effect of ceria on the generation of atomically dispersed transition metal-based catalysts, (iii) experimental and theoretical evidence of the effect of Ce3+ ↔ Ce4+ redox pain on radical scavenging, (iv) the effect of the Ce 4f electrons on the d-band center and electron transfer between Ce to the N-doped carbon and transition metal catalysts for enhanced ORR activity, and (v) the effect of Pt/CeO2/carbon heterojunctions on the stability of the Pt/CeO2/carbon electrocatalyst for ORR. Among several strategies of synthesizing Ce/CeO2 electrocatalysts, the metal–organic framework (MOF)-derived catalysts are being perused extensively due to the tendency of Ce to readily coordinate with O- and N-containing ligands, which upon undergoing pyrolysis, results in the formation of high surface area, porous carbon networks with atomically dispersed metallic/clusters/nanoparticles of Ce active sites. This review paper provides an overview of recent advancements regarding Ce/CeO2-based catalysts derived from the MOF precursor for ORR in fuel cells and metal–air battery applications and we conclude with insights into key issues and future development directions.

Developing Pt-free electrocatalysts is the main solution for reducing the intolerable cost of hydrogen production through the hydrogen evolution reaction (HER), while sustaining rare-earth elements. Thus, we have synthesized carbon nanoflakes derived from carbon cloth doped with controllable boron atoms (Bx/C), where x refers to boron atomic contents (x = 3.42, 5.04, 9.79, and 14.64 wt.%), driven by the impregnation of carbon cloth containing polyester (CC) in an aqueous solution of boric acid, followed by drying at 80 °C for 1 h and then calcination at 500 °C for 2 h under nitrogen. The method allows the conversion of one-dimensional CC to a two-dimensional flake-like structure, in situ enriched with B-C motifs as active sites for HER. The HER performance depends on interfacial interaction of boron with carbon, but B1/C (B = 3.42 wt %) was the optimum with a HER current of 370 mA/cm2 at −0.78 V, overpotential at 10 mA/cm2 (ƞHER@10) of 372 mV, Tafel slope of 166 mV/dec, and stability for 60 h, besides a hydrogen production rate of 1.57 mol·g−1·h−1 of catalyst, due to endowing surface area, intermolecular charge transfer, and electrical conductivity. The data obtained may pave the way for designing heteroatom-integrated carbon from biomass for promoting low-cost HER.

Pt–transition metal intermetallic compounds have been recognized as promising catalysts for oxygen reduction reaction (ORR). However, further enhancing the activity and durability of this kind of catalyst is still necessary. Herein, we report a novel L10-type PtFe intermetallic nanoalloy with the partial substitution of Fe sites by La as a highly active and stable catalyst towards ORR. This new intermetallic nanoalloy retains an ordered structure after the incorporation of La confirmed by XRD, XPS and TEM results and the ordered PtFe0.5La0.5 nanoparticles are embedded in porous carbon (L10-PtFe0.5La0.5@C) in very uniform particle size of around 2 nm. This L10-PtFe0.5La0.5@C catalyst exhibits a half-wave potential of 933 mV, which is about 12 mV and 70 mV higher than those of L10-PtFe@C and commercial Pt/C catalysts, respectively. Moreover, it also achieves an enhanced mass activity of 0.79 A mgPt−1 at 0.90 V, which outperforms the performance of commercial Pt/C (0.10 A mgPt−1). In addition, it also shows excellent stability with only 3 mV negative shift in half-wave potential after 20k CV cycles of accelerated durability testing. This high activity and stability may be attributed to the incorporation of La in the PtFe lattice, which induces the formation of a compressively strained Pt overlayer in acidic media which not only tunes the surface strain of Pt sites but also possesses robust resistance to the dissolution of Fe and La. This work also provides a new direction for the development of Pt-based intermetallic catalysts for efficient catalysis applications.