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• Mo is successfully doped into SrCo 0.5 Fe 0.5 O 3-δ perovskite oxides using a modified sol-gel method. • SrCo 0.5 Fe 0.4 Mo 0.1 O 3-δ requires ∼200 and ∼310 mV overpotentials to reach 10 mA cm−2 for HER and OER. • A current density of 10 mA cm−2 could be achieved by applying a potential of 1.68 V vs. RHE in the SCFM10||SCFM10 electrolyzer. • SrCo 0.5 Fe 0.4 Mo 0.1 O 3-δ exhibits remarkable stability for HER and OER in alkaline electrolyte. Perovskite oxides with high electrocatalytic activities and cost-effectiveness can be developed by rational doping. Here, we fabricate a series of perovskite oxides comprising SrCo 0.5 Fe 0.5-x Mo x O 3-δ (x = 0, 0.05, 0.10, 0.15) doped with different proportions of Fe and Mo elements to enhance the long-term stabilities and electrocatalytic activities for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Among them, SrCo 0.5 Fe 0.4 Mo 0.1 O 3-δ (SCFM10) exhibits the optimum electrocatalytic activity for water splitting, exhibiting overpotentials at −10 mA cm−2 and 10 mA cm−2 of ∼200 mV for HER and ∼310 mV for OER, respectively, generating a current density of 10 mA cm−2 using only 1.68 V in a two-electrode electrolytic cell. Additionally, SCFM10 demonstrates outstanding stability, maintaining continuous operation for 100 h without visible decay. These results give some new points of view into the development of bifunctional catalysts for the purpose of efficient water splitting in a sensible way. [Display omitted] [ABSTRACT FROM AUTHOR]

Antimony (Sb) as a low-toxic and cost-effective metal is a promising material to catalyse CO 2 electroreduction to formate with practical viability. However, monometallic Sb suffers from intrinsically low catalytic activity and the competing hydrogen evolution. Here, we report nanoporous Sb-Bi alloys for substantially improving the catalytic activity of Sb and suppressing hydrogen evolution. The optimal Sb-Bi alloy exhibits a maximum Faradaic efficiency of 95.8 % toward formate production, surpassing the 11.6 % of monometallic Sb counterpart. Operating the catalyst in the flow cell demonstrates a formate partial current density of 734 mA cm−2 and cathodic energy efficiency of 59 % at a moderate overpotential of 800 mV, representing a record formate-production performance so far. Experimental and theoretical studies indicate that the Sb-Bi interactions activate Sb sites to selectively stabilize *OCHO intermediates, facilitating CO 2 -to-formate conversion. This work offers insights in manipulating bimetallic interactions to transform inert materials into active catalysts for efficient electrocatalysis. [Display omitted] • Sb-Bi interactions induce electrocatalytic switching from HER to CO 2 ER. • Sb 2 Bi 6 exhibits a maximum formate selectivity of 95.8 % in an H-type cell. • Sb 2 Bi 6 achieves a record formate activity of 734 mA cm−2 in a flow cell. • Sb-Bi interactions facilitate Sb sites to stabilize *OCHO for formate formation. [ABSTRACT FROM AUTHOR]

Coralloid-Pt nanodendrites decorated nanoporous gold films (NPG-Ptx) were fabricated through underpotential deposition/in-situ reduction replacement (UPD/IRR) strategy and exhibit significantly enhanced ORR activities. Ab initio density functional theory (DFT) studies further demonstrate the ORR mechanism of NPG-Ptx. [Display omitted] • Coralloid-Pt nanodendrites decorated nanoporous gold films (NPG-Ptx) were fabricated through underpotential deposition/in-situ reduction replacement (UPD/IRR) strategy. • The NPG-Ptx (x = 1 ∼ 4) exhibit significantly enhanced ORR activities in acidic media. • The DFT studies demonstrate the ORR mechanism and rate-determining step of NPG-Ptx follow the free energy diagrams. • The PDOS results indicate a relatively stronger O 2 reaction capacity on Pt side than Pt top. Deposition of trace amounts of Pt onto nanoporous gold ligaments (NPG-Pt) has demonstrated promising performance of low-Pt electrocatalysts for oxygen reduction reaction (ORR); however, improving the activity of ORR remains challenging because of the difficulty in understanding the electronic effect between Pt and NPG as well as the absence of ORR mechanism studies on NPG-Pt. Here we show that NPG-Ptx (x = 1 ∼ 4), unique coralloid-Pt nanodendrites decorated nanoporous gold films through underpotential deposition/in-situ reduction replacement (UPD/IRR) strategy, exhibit significantly enhanced ORR activities. Among them, NPG-Pt3 exhibits the best ORR activity compared with the others and Pt/C in acidic media. Density functional theory (DFT) studies demonstrate the ORR mechanism and rate-determining step of NPG-Ptx follow the free energy diagrams. Furthermore, the projected density of state (PDOS) results reveal a relatively weaker O 2 reaction capacity on the top side of Pt (Pt top) than the side site (Pt side) for NPG-Ptx. The increase of d -band center for NPG-Ptx pushes up the energy of the antibonding state above the Fermi level, and then the backflow of electrons into the system makes the energy more stable, optimizing the ORR activity. These results provide new inspirations for the development of low-Pt electrocatalysts for energy technologies in a rational manner. [ABSTRACT FROM AUTHOR]

Advancing the development of economical, high-performance, and durable non-precious metal electrocatalysts for oxygen evolution reaction (OER) holds critical significance. This study presents a self-supporting ternary metal phosphide (NiCoFe–P/NF) electrode developed by direct phosphating metal-organic frameworks (MOFs) precursor. Benefiting from a three-dimensional hierarchical porous structure, optimized electronic configuration, high electrical conductivity, and synergistic effect of multiple elements, the synthesized NiCoFe–P/NF electrocatalyst exhibits exceptional catalytic performance compared to the monometallic or bimetallic phosphides, achieving a low overpotential of 209 mV and a Tafel slope of 29 mV dec−1 at 10 mA cm−2 in 1 M KOH solution. In addition, the prepared catalyst exhibits superior stability and durability, as evidenced by its well-preserved morphology after 48 h of stability test. Furthermore, at a high current density of 100 mA cm−2, the long-term efficiency remains >90% even after 96 h. Density functional theory (DFT) calculations reveal that the high catalytic performance of the NiCoFe–P/NF catalyst is ascribed to modified electronic states and lower adsorption energy to the related species. This study not only presents the synthesis of extremely stable and active OER catalysts but also offers a novel and practical method for the development of new catalysts. [Display omitted] • Self-supporting trimetallic phosphide was investigated for OER. • NiCoFe–P/NF electrode provides superior OER activity and stability. • DFT calculations explain the origin of the high catalytic activity. • A chemically uniform trimetallic two-dimensional MOF served as the precursor. [ABSTRACT FROM AUTHOR]

Catalysts with multifunctional catalytic properties hold great promise in energy conversion and environmental remediation. Herein, a series of 1D hollow NiO/Bi 2 Mo x W 1−x O 6 (x = 0, 0.25, 0.5, 0.75, 1) nanofibers are fabricated via pyrolysis of electrospinning precursor. Integrating the hollow structural merits of large specific surface area, abundant active sites, and built-in electric field, this novel NiO/Bi 2 Mo x W 1−x O 6 nanofibers act as a bifunctional platform boosting photocatalytic tetracycline conversion and electrocatalytic oxygen reduction. NiO/Bi 2 Mo 0.75 W 0.25 O 6 solid solution nanofiber delivers a 99.5 % photocatalytic degradation in 120 min for tetracycline (TC) solution with attractive stability, outperforming its NiO/Bi 2 MoO 6 or NiO/Bi 2 WO 6 counterparts. Radical trapping experiments show that ∙ O 2 ⁻ is the key oxidative radical in the photocatalytic reaction. Moreover, the NiO/Bi 2 Mo 0.75 W 0.25 O 6 solid solution nanofiber exhibits an improved ORR activity in alkaline media with a half-wave potential of 0.63 V, and Tafel slope of 76 mV dec−1, along with high stability. We expect this work to inspire the design of multi-functional catalysts for photocatalytic water treatment and electrocatalytic energy conversion. • 1D NiO/Bi 2 Mo x W 1−x O 6 (x = 0, 0.25, 0.5, 0.75, 1) nanofibers are fabricated via a pyrolysis of electrospinning precursor. • This NiO/Bi 2 Mo x W 1−x O 6 nanofibers act as a bifunctional platform boosting photocatalytic and electrocatalytic reduction. • NiO/Bi 2 Mo 0.75 W 0.25 O 6 solid solution nanofiber delivers a 99.5 % photocatalytic degradation in 120 min for TC solution. • NiO/Bi 2 Mo 0.75 W 0.25 O 6 solid solution nanofiber exhibits an improved ORR activity and high stability in alkaline media. [ABSTRACT FROM AUTHOR]

The pursuit of a desirable photocatalytic technology has always been accompanied by photocatalyst design and development, marking high activity, long-term stability, and low cost. Herein, an in-situ deposition approach is used to integrate plasmonic 0D Ag nanoparticles on the surface of 2D slice-like 2,9,16,23-tetranitrocopper(II) phthalocyanine (CuPc) sensitized 1D Bi 2 MoO 6 nanofibers (Ag-CuPc/Bi 2 MoO 6) for visible-light-induced tetracycline (TC) photocatalysis. Benefiting from the combination of 2D CuPc sensitization, and surface plasmon resonance (SPR) effect of 0D Ag nanoparticles, we experimentally find that the Ag-CuPc/Bi 2 MoO 6 nanofibers boost the visible-light utilization efficiency, promote charge transfer, and separation, and accelerate electron redox transformation in TC photocatalysis. The superior photocatalytic activity is attributed to the strong interfacial interaction, and Z-scheme heterojunction synergy in Ag-CuPc/Bi 2 MoO 6 nanofibers. This work opens new horizons for the delicate design of promising Z-scheme visible-light photocatalysts for the removal of antibiotics in wastewater, realizing water purifications. A novel Ag-decorated CuPc/Bi 2 MoO 6 nanofiber heterojunction photocatalyst was successfully synthesized. Benefiting from the combination of the CuPc sensitization, and the SPR effect of Ag nanoparticles, Ag-CuPc/Bi 2 MoO 6 boosts visible-light utilization efficiency, and promotes the separation efficiency of photogenerated carriers. Therefore, the photocatalytic activity of Ag-CuPc/Bi 2 MoO 6 was improved significantly in tetracycline degradation. [Display omitted] • A novel plasmonic Ag-decorated CuPc/Bi 2 MoO 6 nanofiber was successfully fabricated. • The separation efficiency of e−/h+ was enhanced due to the sensitization of CuPc, and SPR effect of Ag nanoparticles. • Ag-CuPc/Bi 2 MoO 6 exhibited excellent properties in TC degradation. • A possible Z-scheme photocatalytic mechanism was evidenced by MS and ESR analysis. [ABSTRACT FROM AUTHOR]

Given its superior structure, the abundance of surface functional groups, and low cost, cotton fiber filtration paper can be used as the support for hydrogen evolution reaction (HER) and oxygen evolution reaction catalysts (OER) instead of copper foam (CF), nickel foam (NF), or carbon cloth (CC). Herein, the chemical plating method was used to create thin self-supporting electrodes based on cotton fiber filtration paper (FP). The Co-Ni-P amorphous nanospheres can be uniformly dispersed on the self-supporting FP due to its porous structure and oxygen functional groups. The Co-Ni-P/FP electrode has an overpotential as low as 125 mV for HER and 320 mV for OER at the current density of 10 mA cm−2. Additionally, according to density functional theory (DFT) calculations, the Co atom added to the Ni-P nanosphere can lead to considerably more charge accumulation around the Co and Ni active sites, which greatly encourages the HER and OER processes. The novel porous support, FP, provides a fresh way the preparation of self-supporting electrodes. [Display omitted] • Filter paper is used to prepare the self-supporting electrode as the substrate. • The preparation method is simple and the properties are stable. • Rich oxygen-containing functional groups of FP promote deposition and dispersion. • Explore the excellent electrochemical performance of amorphous Co-Ni-P/FP by DFT. [ABSTRACT FROM AUTHOR]

• 1D MWO 4 (M = Zn, Ni, Cu) nanomaterials were synthesized by electrospinning method. • CuWO 4 nanotubes exhibited superior degradation performances under UV–Vis-NIR light. • NIR responses of CuWO 4 and NiWO 4 were explained by metal ion d-d orbital transition. Photocatalysis is a promising technology for addressing environmental pollution and energy shortages in a carbon neutral way, and highly effective utilization of solar light is very important for water treatment via photocatalysis. In this study, we synthesized one-dimensional wolframite-structured MWO 4 (M = Zn, Ni, and Cu) nanomaterials as UV–Vis–NIR broad spectrum-driven photocatalysts via the electrospinning method, and observed the excellent performances in the photocatalytic degradation of tetracycline (TC) and bisphenol A (BPA) under the UV–Vis–NIR light illumination. The degradation experiments showed that CuWO 4 nanotubes exhibited the highest degradation capability, and achieved the TC removal rates of 91.8% and 94.2% after 140 min and 12 h under UV–Vis and NIR light irradiation, respectively. The UV–Vis–NIR responsive photocatalytic activities and mechanisms could be explained by the charge transfer mechanism and metal ion d-d orbital transition based on the experimental results and density functional theory modulations. Our findings demonstrate that the MWO 4 (M = Zn, Ni, and Cu) photocatalysts could be responsive to the UV–Vis–NIR broad-spectrum lights, representing a major step forward in the development of photocatalytic technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchical 1D/2D Ni(OH) 2 /PCC is fabricated via a facile hydrothermal route as the positive electrode. • The porous corn stigma-derived carbon with the 3D open framework is preparated as the negative electrode. • Explore the excellent electrochemical performance of 1D/2D Ni(OH) 2 /PCC by DFT. • The hybrid supercapacitor displays supeiror energy and power density. Enhancing the energy density of supercapacitors is of great scientific and technological importance, producing a larger energy density than traditional symmetrical carbon supercapacitors. Herein, a hybrid supercapacitor based on an activated corn stigma-derived carbon (PCC) electrode combined with a large-capacity faradic 1D nanofiber/2D nanosheet Ni(OH) 2 electrode is designed to fulfill this goal. Benefiting from the highly conductive, porous construction, and 3D open framework of PCC electrode couple with unique hierarchical 1D nanofiber/2D nanosheet Ni(OH) 2 , such 1D/2D Ni(OH) 2 /PCC electrode is capable of increasing accessible active sites, shortening ion-diffusion path, and accelerating mass transfer. More importantly, DFT calculations unveil that 1D/2D Ni(OH) 2 /PCC composites own high electrical conductivity and OH– adsorption energy. Therefore, the specific capacity of the 1D/2D Ni(OH) 2 /PCC composite electrode reaches 655.9C g−1 at the current density of 1 A/g. Moreover, such hybrid 1D/2D Ni(OH) 2 /PCC||PCC supercapacitor show an outstanding energy density and power density of 38.6 Wh kg−1, and 1.03 kW kg−1, respectively. This work provides the possibility of fabricating hierarchical hydroxide/bio-carbon as a better electrode for high-energy–density electrochemical supercapacitors. [ABSTRACT FROM AUTHOR]

Semiconductor-based photocatalyst serves as an attractive candidate for harnessing solar energy to generate renewable hydrogen via water splitting. Here, a novel Au/SrTiO 3 /TiO 2 (T3) photocatalyst of 3D SrTiO 3 /TiO 2 hollow nanosphere decorated by plasmonic Au nanoparticle (NP) is precisely constructed via an in-situ growth of cubic SrTiO 3 on anatase TiO 2 hollow nanospheres. By carefully regulating the SrTiO 3 /TiO 2 interface structure, the optimized Au/SrTiO 3 /TiO 2 (T3) photocatalyst achieves a remarkable photocatalytic H 2 evolution rate of 327.8 μmol g−1 h−1 without Pt as cocatalyst. Specifically, spectroscopic analyses and characterization results comprehensively prove that the favorable plasma electric field (Au) and the internal electric field (SrTiO 3 /TiO 2 heterojunction) coupled with the 3D electron transfer channel in 3D Au-SrTiO 3 /TiO 2 hollow nanospheres synergistically promote the interfacial charge separation and accelerate the interfacial transfer of charge carriers for efficient solar-driven photocatalytic H 2 evolution. This work presents a new strategy for the rational design of plasmonic metal functionalized 3D heterojunction photocatalysts for highly efficient solar-to-chemical energy conversion. [Display omitted] • Au-SrTiO 3 /TiO 2 hollow nanospheres are prepared for photocatalytic water splitting. • 3D hollow sphere unit structure provides electron transfer channels. • The plasma effect and internal electric field promote charge separation and transfer. • Au/SrTiO 3 /TiO 2 photocatalyst achieved a remarkable photocatalytic H 2 evolution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchical NiC 2 O 4 /Ni(OH) 2 nanospheres are synthesized via a simple two-step hydrothermal method as the positive electrode. • The porous biomass-derived carbon with the honeycomb structure is obtained from pine petals as the negative electrode. • Hierarchical NiC 2 O 4 /Ni(OH) 2 nanospheres and the porous biomass-derived carbon possess a high specific capacity. • The hybrid supercapacitor exhibits excellent energy and power density. The high-performance hybrid supercapacitor (HSC) with high power capability and stable cyclability is intensively pursued as a next-generation energy storage device. Here, a kind of hierarchical NiC 2 O 4 /Ni(OH) 2 nanospheres, consisting of subunits of NiC 2 O 4 nanorods and Ni(OH) 2 nanospheres, are synthesized via a two-step hydrothermal method. The hierarchical NiC 2 O 4 /Ni(OH) 2 nanosphere positive electrode, benefiting from the synergistic effect of unique hierarchical structure and built-in electric fields, significantly boosting electron transmission capability and accelerating the ion/electron transfer rate, delivers an excellent specific capacity of 668 C g−1 at 1 A g−1. In addition, the porous biomass-derived carbon (PBC) with the honeycomb structure from pine petals as the negative electrode shows a remarkable electrochemical performance, exhibiting a specific capacitance of 249.7 F g−1 at 1 A g−1. As such, an assembled HSC of NiC 2 O 4 /Ni(OH) 2 ||PBC based on hierarchical NiC 2 O 4 /Ni(OH) 2 nanospheres positive electrode and PBC negative electrode display a conspicuous energy density of 31.07 Wh kg−1, and a power density of 833.47 W kg−1 at a maximum potential window of 1.7 V. This innovative hierarchical engineering of double nickel-based composites with bio-carbon provides an advanced enlightenment for high-performance HSCs. [ABSTRACT FROM AUTHOR]

• Co 3 V 2 O 8 -T (T = temperature/°C) are prepared as bifunctional electrocatalysts. • Co 3 V 2 O 8 -400 nanofibers show small Tafel slopes of 43 and 63 mV dec−1 for ORR and OER. • The Co 3 V 2 O 8 -400 nanofiber has the best catalytic activities for ORR and OER. • The mechanism of Co 3 V 2 O 8 -400 nanofiber is simulated by DFT. Highly active and stable bifunctional electrocatalysts towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are necessary for practical fuel cells, metal-air batteries, and water splitting. Herein, we report a series of bifunctional Co 3 V 2 O 8 -T (T = temperature/°C) electrocatalysts by using Co-carbon electrospun nanofiber as a template, followed by a one-step calcination process. As expected, the developed Co 3 V 2 O 8 -400 nanofiber electrocatalyst shows a very small Tafel slope of 43 and 63 mV dec−1 for the ORR and OER in the alkaline solution, respectively. In addition, density functional theory (DFT) calculations reveal that the metallic conductivity and interface V-Co interaction of Co 3 V 2 O 8 -400 nanofiber boost ORR and OER electrocatalytic reactions. [ABSTRACT FROM AUTHOR]