The investigation of cost-effective and highly efficient electrocatalysts for alkaline water and simulative seawater oxidation is essential to the conversion and storage of renewable energy. In this ...paper, the Ce–NiSe2/CoP catalyst with multihole and ultrathin nanosheet structure is generated. The unique structural characteristics of Ce–NiSe2/CoP heterojunction nanosheets contribute the excellent OER performance under different alkaline 1 M KOH and simulated seawater (1 M KOH + 0.5 M NaCl) electrolytes. Specifically, this catalyst exhucture is generated. The unique structural characteristics of Ce–NiSe2/CoP heterojunction nanosheets conibits the low overpotentials of 287 and 304 mV at the current density of 10 mA cm−2, along with the Tafel slopes of 87.1 and 78.8 mV dec−1 in two solutions, respectively. Moreover, the Ce–NiSe2/CoP target product also displays good stability. The present study introduces a promising strategy for the advancement of high-performance electrocatalysts in green energy field.
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•The Ce-doped NiSe2/CoP heterostructure nanosheets are triumphantly generated.•The Ce–NiSe2/CoP product possesses multihole and ultrathin lamella architecture.•Each nanosheet with coarse surface is composed of prolifically nanosecondary units.•This catalyst presents fine OER properties in alkaline water and simulative seawater.
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•Dual-phase CoP-CoTe2 nanowires are used as bifunctional catalysts for HER and OER.•The introduction of CoP phase markedly enhances the electrocatalytic performance.•BPM water ...electrolysis is demonstrated using CoP-CoTe2 nanowires as catalysts.•BPM water electrolysis under forward bias requires substantially low external bias.•BPM water electrolysis shows outstanding long-term stability.
Electrochemical water splitting powered by renewable energy (e.g. solar, wind) has been recognized as a sustainable and environmentally-friendly way to produce “green” hydrogen. Significant efforts were dedicated recently to developing cheap and efficient earth-abundant electrocatalysts to make electrolyzed hydrogen economically competitive. Notwithstanding substantial progress, the operational voltage of water splitting in a single electrolyte system is still high, even highly efficient electrocatalysts are used to catalyze the hydrogen evolution (HER) and oxygen evolution reactions (OER). Taking into account that the HER and the OER are kinetically favorable in electrolytes with different pH values, in this work we demonstrate that overall water splitting can be accomplished in acid-alkaline dual electrolytes with an onset voltage as low as 1.13 V, enabled by a bipolar membrane (BPM) under the “reverse bias” condition with the novel dual-phase cobalt phosphide-cobalt ditelluride (CoP-CoTe2) nanowires being used as efficient and durable bifunctional catalysts. Furthermore, we show that using a BPM under the “forward bias” the voltages needed to reach 10 and 100 mA cm−2 can be reduced to 1.01 and 1.37 V, respectively, due to the assistance of electrochemical neutralization resulting from the crossover of electrolytes. The bipolar membrane water electrolysis (BPMWE) can be sustained for at least 100 h without notable degradation.
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Developing a highly effective bifunctional electrocatalyst for alkaline-condition electrochemical water splitting is both essential and challenging. The work presented here ...successfully synthesizes and employs a heterostructured CoP-NiCoP ultra-long nanopin array in situ growing on MXene (Ti3C2Tx) as a stable bifunctional electrocatalyst for electrochemical water-splitting. The heterogeneous structure formed by CoP nanoparticles and NiCoP nanopins provides extra active sites for water-splitting. Also, Ti3C2Tx works as a support substrate during electrochemical operations, accelerating mass transfer, ion transport, and rapid gas product diffusion. Meanwhile, throughout the catalytic process, the dense nanopin arrays shield Ti3C2Tx from further oxidation. At a result, the CoP-NiCoP-Ti3C2Tx (denoted as CP-NCP-T) demonstrated excellent catalytic activity, with overpotentials of just 46 mV for hydrogen evolution at 10 mA cm−2 and 281 mV for oxygen evolution at 50 mA cm−2. Furthermore, in 1.0 M KOH solution, the outstanding bifunctional electrode (CP-NCP-T || CP-NCP-T) exhibits efficient electrochemical water splitting activity (1.54 V@10 mA cm−2) and outperforms the comparable device Pt/C || IrO2 (1.62 V@10 mA cm−2).
Eukaryotic cells employ membrane-bound carriers to transport cargo between compartments in a process essential to cell functionality. Carriers are generated by coat complexes that couple cargo ...capture to membrane deformation. The COPII coat mediates export from the endoplasmic reticulum by assembling in inner and outer layers, yielding carriers of variable shape and size that allow secretion of thousands of diverse cargo. Despite detailed understanding of COPII subunits, the molecular mechanisms of coat assembly and membrane deformation are unclear. Here we present a 4.9 Å cryo-tomography subtomogram averaging structure of in vitro-reconstituted membrane-bound inner coat. We show that the outer coat (Sec13-Sec31) bridges inner coat subunits (Sar1-Sec23-Sec24), promoting their assembly into a tight lattice. We directly visualize the membrane-embedded Sar1 amphipathic helix, revealing that lattice formation induces parallel helix insertions, yielding tubular curvature. We propose that regulators like the procollagen receptor TANGO1 modulate this mechanism to determine vesicle shape and size.
Distinct trafficking pathways within the secretory and endocytic systems ensure prompt and precise delivery of specific cargo molecules to different cellular compartments via small vesicular (50–150 ...nm) and tubular carriers. The COPI vesicular coat is required for retrograde trafficking from the cis -Golgi back to the ER and within the Golgi stack. Recent structural data have been obtained from X-ray crystallographic studies on COPI coat components alone and on COPI subunits in complex with either cargo motifs or Arf1, and from reconstructions of COPI coated vesicles by electron tomography. These studies provide important molecular information and indicate key differences in COPI coat assembly as compared with clathrin-based and COPII-based coats.
•CoP-Fe2O3/g-C3N4 improve photogenerated electron–hole separation efficiency.•CoP-Fe2O3/g-C3N4 decrease ROS generation in MES.•CoP-Fe2O3/g-C3N4 provide more reducing force to improve MES ...performance.•CoP-Fe2O3/g-C3N4 facilitated the enrichment of microorganisms.•142.20 mg/L PHB can be obtained on 7-day MES reaction.
The hydrogen energy and CO2 reduction in-situ recombination has drawn increasing attention. Microbial electrosynthesis (MES) integrated with photocatalytic materials is a novel technology for CO2 utilization. Here, MES with the photocathode CoP-Fe2O3/g-C3N4 was constructed using Ralstonia eutropha as biocatalyst to generate polyhydroxybutyrate (PHB). The integration of CoP and Fe2O3/g-C3N4 facilitated electron–hole pair separation and electron transfer, which enhanced hydrogen evolution reaction and provided additional reducing power for CO2 conversion. Simultaneously, the concentration of reactive oxygen species was also considerably reduced, increasing the production of PHB. In particular, 87.54 mg/L of PHB was obtained in CoP-Fe2O3/g-C3N4 at − 1.05 V, which is about three times higher than that in carbon felt. At − 0.9 V, PHB concentration further increased to 142.20 mg/L. This study provides a new approach for converting CO2 into multicarbon compounds in situ electrolysis of water under visible light.
It is still challenging to develop high‐efficiency and low‐cost non‐noble metal‐based electrocatalysts for hydrogen evolution reaction (HER) in pH‐universal electrolytes. Herein, hierarchically ...porous W‐doped CoP nanoflake arrays on carbon cloth (W‐CoP NAs/CC) are synthesized via facile liquid‐phase reactions and a subsequent phosphorization process. The W‐CoP NAs/CC hybrid can be directly employed as a binder‐free electrocatalyst and delivers superior HER performance in pH‐universal electrolytes. Especially, it delivers very low overpotentials of 89, 94, and 102 mV to reach a current density of 10 mA cm–2 in acidic, alkaline, and neutral electrolytes, respectively. Furthermore, it shows a nearly 100% Faradaic efficiency as well as superior long‐term stability with no decreasing up to 36 h in pH‐universal electrolytes. The outstanding electrocatalytic performance of W‐CoP NAs/CC can be mainly attributed to the porous W‐doped nanoflake arrays, which not only afford rich exposed active sites, but also accelerate the access of electrolytes and the diffusion of H2 bubbles, thus efficiently promoting the HER performance. This work provides a new horizon to rationally design and synthesize highly effective and stable non‐noble metal phosphide‐based pH‐universal electrocatalysts for HER.
Hierarchically porous W‐doped CoP nanoflake arrays on carbon cloth (W‐CoP NAs/CC) are synthesized, which deliver highly efficient and stable electrocatalytic performance for hydrogen evolution reaction (HER) in pH‐universal electrolytes, due to the doping effect and porous nanoarchitecture. This work provides a new strategy to design and synthesize non‐noble metal phosphide‐based pH‐universal HER electrocatalysts with high efficiency and excellent stability.
•A facile strategy is proposed to construct CoP/Cu3P heterostructured nanoplate.•The prepared electrode shows an improved specific capacitance and rate capability.•Theoretical calculations further ...confirm the enhanced electrical conductivity.
CoP is considered as a promising electrode material for supercapacitors owing to the concomitant covalent and metallic bonds which lead to high electrical conductivity and high theoretical capacitance. However, the practical low specific capacitance and poor rate capability limit its further applications. Here, a novel CoP/Cu3P heterostructured nanoplate is fabricated via a facile phosphorization process. Due to the synergistic effects of heterostructure, the ionic and electronic diffusion kinetics in the CoP/Cu3P are significantly improved. The CoP/Cu3P electrode manifests an excellent electrochemical performance of 734.2 F g−1 at 1.0 A g−1, a state-of-the-art rate capability of 53.2% capacitance retention even when the current density increases to 50.0 A g−1, and an excellent cycling performance. A hybrid asymmetric device constructed with CoP/Cu3P as positive electrode delivers a high energy density of 28.6 Wh kg−1 at the power density of 775.0 W kg−1, and an ultra-high power density of 38.8 kW kg−1 at 9.7 Wh kg−1. Theoretical calculations further confirm that the heterostructure can effectively tune the electronic structure of CoP and Cu3P, and improve the charge transport. This study provides insight into the rational design of high-rate performance electrode materials in energy storage.
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•CoP/CNx composite photocatalysts were rationally designed and synthesized.•CoP/CNx composite show enhanced photocatalytic degradation of TC.•The possible photodegradation pathways of ...TC was proposed.•The N-defects and CoP co-catalyst synergistically promoted the charge separation efficiency.
The strategies of introducing defect engineering and cocatalysts in designing photocatalysts are both effective at ameliorating photocatalytic activity. In this study, N-defected g-C3N4 (CNx) was added to the preparation process of CoP, where N-defects and loaded CoP cocatalyst were successfully combined to synthesize CoP/CNx composite photocatalysts, which not only strongly expands the visible-light absorption but also effectively restrains the recombination of photoinduced electron holes, hence greatly improving the photocatalytic degradation performance of tetracycline (TC). Experimental results revealed that 5% CoP/CNx has the optimum photocatalytic activity with a degradation rate of 97% within 120 min of visible-light irradiation, which is 6.84 and 4.33 times higher than that of bare CN and CNx, respectively. In addition, the cycling experiments and XRD patterns before and after the photocatalytic reaction showed that the catalyst exhibits outstanding stability, which is conducive to practical applications in the field of photocatalysis. The possible photodegradation pathways of TC were proposed on the basis of the intermediates detected by liquid chromatography-mass spectroscopy (LC–MS). The N-defects in the CN structure and the addition of the cocatalyst CoP synergistically promoted the separation efficiency of the photogenerated charges of the composite and enhanced its photocatalytic activity.
The pseudocapacitive performance of CoP growing on nickel foam is enhanced via surface Ni2P modification and Ni2+ doping technology. The Ni-doped CoP material and CoP/Ni2P composite have been ...fabricated successfully using hydrothermal reaction and phosphating reaction. Due to the coupling effect between the doped ion and cobalt ion, or the two-phase composite effect, Ni-CoP and CoP/Ni2P display excellent electrochemical performance compared with the pristine CoP. At the current density of 1 A g−1, the specific capacities of three as-prepared samples are 403C g−1 for CoP, 578C g−1 for Ni-CoP, and 1557C g−1 for CoP/Ni2P, respectively. The modified electrodes show an obvious advantage in the means of energy storage. Meanwhile, they display great stability. Besides, three asymmetric supercapacitors are also assembled. For the device based on the Ni-CoP, when the current density is 1 A g−1, the power density is 1787 W kg−1 and the energy density reaches 44 W h kg−1. For the device based on the CoP/Ni2P, the power density arrives at 1104 W kg−1 and the energy density is up to 53 W h kg−1. Compared with the data of previous papers about supercapacitors with CoP coating electrodes, their performances are more excellent, implying the adopted tactics in the work are achievable.
•The CoP, Ni-CoP, and CoP/Ni2P coatings on nickel foam is synthesized via a hydrothermal and phosphating reaction.•The coatings on nickel foam are used as supercapacitor electrodes and show remarkable energy storage performance.•Compared with CoP coating, modified samples of Ni-CoP and CoP/Ni2P shows more better pseudocapacitive performance.•Compared with CoP-based supercapacitor, Ni-CoP-based and CoP/Ni2P-based supercapacitors show higher energy densities.
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