One-step Electrodeposition Research Articles

Porous nickel–cobalt phosphate with oxygen-rich vacancies in situ grown on dopamine-modified cellulose textiles as self-supporting high mass loadings supercapacitor electrode

Transition-metal phosphates/phosphides showcase significant promise for energy-related applications because of their high theoretical electrochemical characteristics. However, sluggish electro/ion transfer rates and kinetically unfavorable reaction sites hinder their application at high mass loading. Herein, a self-supporting electrode based on transition-metal phosphates was successfully fabricated via a one-step electrodeposition process. The nanosheet structure of transition-metal phosphates, formed by interconnecting nanoparticles, effectively mitigates the impact of stress and achieves a high mass-loading (21 mg cm−2) of the electrode. Additionally, the oxygen vacancy-rich and porous nanostructure of transition-metal phosphates endows the as-prepared electrodes with a significantly increased conductivity and fast ion migration rate for enhancing electrochemical kinetics. Consequently, the as-fabricated transition-metal phosphate electrode displays the highest areal specific capacity of 39.2F cm−2. Furthermore, the asymmetric supercapacitor achieves a maximum energy density of 0.79 mWh cm−2 and a high capacity retention of 93.0 % for 10000 cycles under 60 mA cm−2. This work provides an ideal strategy for fabricating flexible electrodes with high mass loading and synthesizing transition-metal phosphate electrodes rich in oxygen vacancies.

Environmentally benign bioinspired oleogel infused surface based on edible sunflower seed oil: Preparation and corrosion mitigating for Mg-Li alloy

The production of metals is an essential process to contribute carbon dioxide emission. Being exposed in natural and industrial environment, metal endures corrosion, which in turn leads to significant material loss. Thus, protecting metal from corrosion is not just a matter of material preservation but also a critical aspect for promoting environmental sustainability. Acting as a barrier, traditional organic coating is widely adopted to prevent metal from corrosion. However, over time, the coating degradation contributes to the growing problem of microplastic pollution. Given these concerns, the challenge lies in developing sustainable, environmentally friendly methods for protecting metals from corrosion. Bioinspired slippery liquid-infused porous surface (SLIPS) has emerged as advantageous solutions for corrosion protection. In this study, firstly, a bioinspired superhydrophobic coating is constructed onto a highly active Magnesium-lithium (Mg-Li) alloy via a one-step electrodeposition. Following that, an edible beeswax-sunflower seed oil is used to form a composite oleogel-infused surface (OIS), one category of SLIPS. Traditional characterization, such as high-resolution transmission electron microscopy (HRTEM), and sophisticated X-ray computed tomography (X-CT) reveal the detailed microstructure and composition of the coatings. The corrosion resistance of OIS surfaces significantly surpasses that of superhydrophobic surfaces, as evaluated by scanning Kelvin probe (SKP), electrochemical impedance spectroscopy, and potentiodynamic polarization curve. The OIS exhibits a high corrosion inhibition efficiency of 99.99%, far exceeding that of the superhydrophobic surface. Furthermore, the OIS demonstrates self-healing capability, with waxy components undergoing phase transition to repair surface damage caused by scratching. This environmentally sustainable biomimetic coating affords versatility and long-term corrosion protection for Mg-Li alloy, paving a new way for their extensive utilization in various fields.

Highly-efficient low-voltage electrodeposition of superhydrophobic diamond-like carbon films from N-methyl pyrrolidone

N-methyl pyrrolidone was proposed as a new carbon source for efficiently preparing the diamond-like carbon (DLC) films by a one-step electrodeposition technique at a low voltage. The responses of surface morphology, microstructure and surface wettability of the DLC films on the variation of the area ratio of anode to cathode were investigated in terms of current density in the process of electrodeposition. Especially, the dynamic behaviors of water droplets impacting on one of the superhydrophobic DLC films were studied in detail as a function of Weber number and inclined angle. Results revealed that either a larger or a smaller area ratio than 1.56 could facilitate the formation of hierarchical structure with more hydrocarbon features, which is in favor of creating superhydrophobicity with low surface adhesion. Further, it was found that a competitive strategy between deformation and movement depending on Weber number and inclined angle, where the movement is balanced by sliding with rolling, dominates the impact dynamics of water droplets. This work provides new insight and explanation for the efficient electrodeposition of DLC films at low voltage and the dynamic evolution of impacting droplets on the inclined superhydrophobic surface.

Electrodeposition of Amorphous and Nanocrystalline Ni-Co Alloys of Controlled Composition from Protic Ionic Liquid and Their Use for the Hydrogen Evolution Reaction

In recent years, a growing interest has been paid in developing new and more efficient electrocatalysts for water splitting [1]. This study focuses on the synthesis of amorphous and nanocrystalline Ni-Co alloys through a one-step electrodeposition technique in pure ethylammonium nitrate (EAN), a protic ionic liquid. The use of ionic liquid prevents from the formation of oxide film during the electrodeposition of the metal [2]. However, only few studies involve protic ionic liquids and the use of EAN, in particular, the electrodeposition of Ni/Co-based materials is still scarce. In this work, the physicochemical properties of EAN with different concentrations of Ni2+ and Co2+ salts were investigated, along with the electrochemical behavior of these metal cations in the protic ionic liquid in an aerated atmosphere. Moreover, the redox reversibility of electrochemical systems involving Ni and Co ions were examined by cyclic voltammetry, revealing the formation of an oxide film or side-reactions in the presence of air during electrodeposition, showing the need to prepare these materials in an oxygen-free environment. The deposits have then been characterized by TEM (Figure 1). Nanocrystalline Ni-Co alloys with different atomic ratios were obtained depending on the deposition potential and ion concentrations. We showed that when a higher cathodic potential is applied (-1.3 V/Ag/Ag+), the amorphous Ni51.9Co48.1 alloy could be electrodeposited, instead of nanocrystalline alloys. The XRD and SEM analyses exhibited different morphologies and atomic structures of the synthesized alloys.The electrocatalytic properties of the synthesized materials were investigated towards the hydrogen evolution reaction (HER). The results showed that the addition of Co in Ni-based alloys could enhance the HER, and notably, amorphous Ni-Co alloys exhibited lower overpotential, indicating better reaction abilities and faster reaction rates. The deposited Ni-Co alloys on Cu board also demonstrated good stability during the recycle measurement. This study provides a new pathway for preparing nanocrystalline and amorphous Ni-Co alloys with different ratios using protic ionic liquid, which can have practical applications and good performances in electrocatalysis such as water splitting.[1] M. Zhao, K. Abe, S.-I. Yamaura, Y. Yamamoto, N. Asao, Chem. Mater. 2014(26) 1056-1061.[2] M. Asnavande, C. Zhao, Chem. Mater. 26 (2014) 1056-1061. ACS Sustain. Chem. Eng. 2017 5 (1) 85-89. Figure 1

Electrodeposition of CoSx-graphene nanoplatelets on Ni(OH)2 nanosheets for improving the pseudocapacitance performance

In the present work, binder-free CoSx–graphene nanoplatelets porous structures were coated on Ni(OH)2 nanosheets using a one-step electrodeposition process. The graphene was produced from the electroreduction of CO2∗ intermediates during the electrodeposition of CoSx. The surface morphology and interfacial bonding states of CoSx–graphene@Ni(OH)2 were sensitive to the deposition time and Co–to–thiourea molar ratio (Mr). The interface reconstruction between CoSx–graphene NCs and Ni(OH)2 nanosheets improved the pseudocapacitance performance, which was investigated at different Mr and varying deposition times. Raman spectra verified the presence of graphene and CoSx mixed phases in all heterostructure electrodes, where CoS2 was dominant at Mr = 0.2. An XPS analysis indicated the evolution of various interfacial bonding states (CO, CO, CoONi, and SO) between Ni(OH)2 nanosheets and CoSx-graphene nanoplatelets, revealing the improvement in the interfacial synergy and concentration of electroactive sites. The hybrid CoSx-graphene@Ni(OH)2 NCs at Mr = 0.2 exhibited the highest capacitance of 2116 F∙g−1 at 2 mV∙s−1 and 1618 F∙g−1 at 1 A∙g−1 compared with bare Ni(OH)2, which achieved 1212 F∙g−1 at 2 mV∙s−1 and 882.88 F∙g−1 at 1 A∙g−1, and other NCs. Bare Ni(OH)2 nanosheets retained only capacitance retention of 25 % after 2000 cycles, which improved to 70 % in all CoSx-graphene@Ni(OH)2 nanoplatelets.

Boosting alkaline/neutral hydrogen evolution reaction of nickel selenium by introducing carbon dopants

Searching for efficient, cost-effective, and durable nonprecious electrocatalysts for hydrogen evolution reaction (HER) is extremely desirable in sustainable and renewable energy researches, but remains highly challenging in recent decades. Herein, a novel Nickel-Selenium-Carbon (Ni-Se-C) electrocatalysts fabricated on nickel foam are produced by a one-step facile electrodeposition method. Under the optimum conditions, the Ni-Se-C electrocatalyst displays extraordinary performance with ultralow HER overpotentials of 68 and 219 mV at 10 mA·cm−2 under alkaline or neutral conditions, respectively, as well as excellent durability. Besides, the Ni-Se-C electrocatalyst has demonstrated a reduction in the activation energy (Ea) of HER (26.0 kJ·mol−1) in comparison to the Ni-Se electrocatalyst (33.1 kJ·mol−1). The introduction of C has a beneficial effect of reducing the electron density around Ni and Se, which in turn adjusts the electronic structure of the Ni-Se-C electrocatalyst. This accelerates the efficiency of electron transfer and exposes more surface catalytic active sites, thereby significantly improving the HER performance of the Ni-Se-C electrocatalyst. In addition, the doping of C can also adjust the hydrophilicity of the electrocatalyst surface, which facilitates the detachment of bubbles and quickly re-expose the active sites. This finding offers guidance and inspiration to produce low-cost and extremely effective nonprecious HER electrocatalyst for industrial hydrogen production.

Rational regulation and one-step electrodeposition realization of surface textures and free energy to create mechanochemically durable superhydrophobicity for the enhanced anti-icing properties

The quest for durable superhydrophobic materials with exceptional water-repellent properties remains a pressing challenge. This study introduces an innovative methodology that exploits one-step electrodeposition realization of surface textures and free energy to create robust superhydrophobic surfaces. Leveraging copper, nickel, and polytetrafluoroethylene nanoparticles, a dendritic microstructure is fabricated. An unprecedented feature of this process is the controlled partial melting of polytetrafluoroethylene during sintering, enabling the connection of discrete polymer particles and the formation of a resilient coating skeleton. This pioneering method grows low-energy materials in situ between coatings and gives the surface greater robustness. The surface prepared by this method showed excellent non-wettability, highlighted by a remarkable water contact angle of 163.1°. The surface shows outstanding anti-icing performance: water droplets resist freezing for up to 1173 s at −20 °C with negligible ice adhesion (only 34 kPa). Importantly, this technique is amenable to large metal surfaces. This study presents a novel and effective solution to face the durability challenges (The sample can withstand 400 linear wear and is resistant to acids, alkalis and ultraviolet). It underscores the innovative fusion of micro-nanostructure construction and low surface energy material modification, promising both enhanced adhesion and the preservation of surface durability.

The electrical conductivity mechanism of Graphene/Copper composite fabricated by one-step pulsed electrodeposition

Copper plays a key role in electronics, energy, and so on. However, copper faces the challenge of increasing resistivity with increasing temperature. To overcome this problem, graphene was introduced into copper to prepare graphene/copper (Gr/Cu) composites. Here, we report on the preparation of Gr/Cu-Cu wires and Gr/Cu foil by pulse electrodeposition (P-EP). The electrical conductivity of the Gr/Cu foil was 3.8 % IACS higher than that of pure Cu foil under 180 °C. Graphene plays a crucial role in providing an electron transfer path in the Gr/Cu composite to improve the electrical conductivity under high temperatures. The P-EP process can not only effectively reduce the raw GO, but also introduce nitrogen into graphene which further promotes the transfer of electrons from copper to graphene. These results suggest that Gr/Cu composites have promising prospects for applications at high temperatures and could potentially replace traditional pure Cu.

Controlled preparation of carbon cloth decorated with nanostructured Mn(OH)2/Mn3O4 electrodes for high-performance asymmetric supercapacitors

Environmentally friendly aqueous asymmetric supercapacitors are expected to exhibit excellent energy storage properties, stable performance, and facile production protocols. This study focused on the fabrication and characterisation of an asymmetric supercapacitor (ASC) with a commercial activated carbon (AC) negative electrode and Mn(OH)2/Mn3O4 composite on carbon cloth (hCC) positive electrode. The Mn-based electrode was synthesised using a one-step electrodeposition process. The morphology and crystalline structure of the composite electrode were modified by varying the deposition time of the Mn(OH)2/Mn3O4 nanostructures on carbon cloth substrate which greatly influence the electrochemical performance of the asymmetric systems. The best ASC used the AC electrode and a Mn(OH)2/Mn3O4@hCC electrode prepared using electrodeposition over an optimised time of 3 h. It exhibited a remarkable specific energy density of 40.7 Wh kg−1 at a power density of 100 W kg−1. In addition, this ASC demonstrated stable long-term performance, retaining 88 % of its capacitance after 5000 charge–discharge cycles, showing its great application potential in the field of supercapacitors.

Electrodeposition in one step: Synthesizing Ir–Co tetradecahedral nanoparticles with high-index (311) crystal planes for enhanced catalytic activity in alkaline hydrogen evolution reaction

Electrochemical water splitting represents a viable route for hydrogen production, but its efficiency critically depends on developing effective electrocatalysts that minimize energy loss and material costs. This study introduces iridium-cobalt (Ir–Co) nanoparticles were synthesized on copper foam (CF) substrates using a one-step electrodeposition method. A comprehensive analysis was conducted on the morphology, chemical composition, and crystal structure of the electrocatalysts, along with a particular study on their electrocatalytic performance in the hydrogen evolution reaction (HER). The results demonstrate that high-index IrCo (311) crystal planes have been detected in the Ir–Co/CF electrocatalysts, which possess a tetradecahedral polycrystalline structure. The size of tetradecahedral nanoparticles is in the range of 180–250 nm. Ir–Co nanoparticles exhibit a balanced composition of approximately 49.8 at% Ir and 50.2 at% Co. The Ir–Co/CF electrocatalyst exhibits superior electrocatalytic activity in 1.0 M KOH solution, requiring only 46.8 mV overpotential to obtain a current density of 10 mA cm−2, with a low Tafel slope of 32.65 mV·dec−1. Additionally, the prolonged stability tests confirm the robustness of the Ir–Co/CF electrocatalyst, highlighting its potential for sustainable energy applications.

Electrodeposition of myristate based superhydrophobic coatings on steel with enhanced corrosion resistance and self-cleaning property

In recent decades, superhydrophobic (SHP) coatings have gained significant attention because of their versatile applications. Superhydrophobic coating is considered as a promising solution to combat corrosion and biofouling issues encountered by steel components in various industries. Using a one-step electrodeposition technique, a superhydrophobic coating with strong corrosion resistance and anti-biofouling property was fabricated on carbon steel in this work. With a water contact angle (WCA) of 170.3 ± 4.2° and a sliding angle (SA) of ∼1°, the wettability of the surface was optimized by varying the electrodeposition potential and deposition time. The as-developed superhydrophobic carbon steel surfaces were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), laser Raman spectroscopy (LRS), Energy dispersive X-ray (EDS) spectroscopy and X-ray diffraction (XRD). Employing field emission scanning electron microscopy (FESEM), the morphology of the superhydrophobic coatings was examined. Potentiodynamic polarization (PDP) technique was used to study the anti-corrosion property of SHP coating and bare sample in 3.5 wt% NaCl solution. The superhydrophobic coating was found to exhibit 99 % corrosion inhibition efficiency. In addition, the biofouling resistance of the coating was evaluated in both gram-negative and gram-positive bacterial cultures and compared with the uncoated sample. Total viability count (TVC) for the SHP coated samples was 5 orders less as compared to the uncoated sample exposed to gram-negative bacterial culture. Similarly, 4 orders reduction in TVC was estimated for the SHP coated sample as compared to the uncoated sample in gram-positive bacterial culture. The impact of superhydrophobic coating on the corrosion performance and biofouling properties of carbon steel was investigated along with the self-cleaning property and robustness of the coating.

In Situ Preparation of Metallic Copper Nanosheets/Carbon Paper Sensitive Electrodes for Low-Potential Electrochemical Detection of Nitrite.

In the realm of electrochemical nitrite detection, the potent oxidizing nature of nitrite typically necessitates operation at high detection potentials. However, this study introduces a novel approach to address this challenge by developing a highly sensitive electrochemical sensor with a low reduction detection potential. Specifically, a copper metal nanosheet/carbon paper sensitive electrode (Cu/CP) was fabricated using a one-step electrodeposition method, leveraging the catalytic reduction properties of copper's high occupancy d-orbital. The Cu/CP sensor exhibited remarkable performance in nitrite detection, featuring a low detection potential of -0.05 V vs. Hg/HgO, a wide linear range of 10~1000 μM, an impressive detection limit of 0.079 μM (S/N = 3), and a high sensitivity of 2140 μA mM-1cm-2. These findings underscore the efficacy of electrochemical nitrite detection through catalytic reduction as a means to reduce the operational voltage of the sensor. By showcasing the successful implementation of this strategy, this work sets a valuable precedent for the advancement of electrochemical low-potential nitrite detection methodologies.

One-step electrodeposition of a novel gold nanoparticles/MoS2-graphene nanocomposite based electrochemical sensor for simultaneous determination of tert-butylhydroquinone and butylated hydroxyanisole

The study developed a novel electrochemical sensor based on gold nanoparticles (AuNPs)/MoS2-graphene nanocomposite for simultaneous determination of tert-butylhydroquinone (TBHQ) and butylated hydroxyanisole (BHA). Herein, AuNPs were in situ grown onto the MoS2-graphene oxide (GO) nanocomposite modified electrode by a simple electrodeposition. Meanwhile, the GO was reduced to the higher conductive reduced graphene oxide (RGO) during the electrochemistry process. The prepared AuNPs/MoS2-RGO nanocomposite not only increased the active electrochemical surface area but also improved the current response towards TBHQ and BHA, which exhibited highly sensitive and selective for simultaneous determination of TBHQ and BHA. The proposed sensor showed excellent responses towards TBHQ and BHA in a wide linear range from 1 to 500 μmol·L−1, as well as detection limits of 0.30 μmol·L−1 for TBHQ and 0.25 μmol·L−1 for BHA, respectively. In addition, the sensor was successfully applied for the determination of TBHQ and BHA in different food samples, giving satisfactory recoveries.

The mechanism of enhanced electrocatalytic water splitting on S-doped NiFe2O4/Ni–Fe alloy@copper foams

The development of bifunctional catalysts with subtle structures, high efficiencies, and good durabilities for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is crucial for overall water splitting. In this work, a multicomponent S-doped NiFe2O4/Ni–Fe micro nano flower electrocatalyst was synthesized rapidly on foam copper using a simple one-step constant current electrodeposition method. The introduction of S leads to the transformation of the microsphere structure of the Ni–Fe alloy into a cauliflower-like morphology and induces changes in the surface electronic structure, significantly enhancing the catalytic performance for the HER and OER. The S-NiFe2O4/Ni–Fe alloy/CF showed low overpotentials of 220 and 66 mV at 10 mA cm−2 in 1.0 M KOH for the OER and HER, respectively. High durability OER and HER performances were demonstrated through 60 h of chronopotentiometry and 6000 CV cycles test. Excellent overall water splitting electrocatalytic activity was observed in the S-NiFe2O4/Ni–Fe alloy/CF‖S-NiFe2O4/Ni–Fe alloy/CF two-electrode system. In particular, active-phase NiOOH, a highly active substance for OER, can be controllably formed in the reaction process owing to the nanoflower structure of multi-layer sulfur which slows down the dissolution of NiFe2O4/Ni–Fe alloy. These results suggest that this composite structure is a promising bifunctional electrocatalyst.

One-step electrodeposition of bifunctional MnCoPi electrocatalysts with wrinkled globular-flowers-like structure for highly efficient electrocatalytic water splitting

The development and exploration of electrocatalysts with the high reactive and abundant availability is still extremely crucial in electrocatalytic overall water splitting. Herein, a novel globular-flowers-like MnO2/Co3(PO4)2 (denoted as MnCoPi) electrocatalyst on nickel foam was successfully prepared through a simple one-step electrodeposition method. The MnCoPi electrocatalyst simultaneously delivers remarkable electrocatalytic activities for hydrogen evolution reaction (HER) with overpotentials (η10) reaching 102 mV and oxygen evolution reaction (OER) with overpotentials (η10) up to 225 mV in 1 M KOH solution. Furthermore, the assembled electrolyzer cell utilizing MnCoPi as the cathode and anode only requires a low voltage of 1.55 V to achieve a current density of 10 mA cm−2. Moreover, the developed MnCoPi electrocatalyst shows excellent stability during continuous operation for 48 h in OER, HER and overall water splitting process. Compared with the pristine MnO2, the significant electrocatalytic properties of MnCoPi can mainly be attributed to the improved physicochemical properties such as distinctive globular-flowers-like morphology, huge specific surface areas and abundant porosity structure, low electrochemical resistance, especially for the formed heterojunction between MnO2 and Co3(PO4)2, which can provide abundant reactive sites and accelerated electron transfer, etc. Consequently, this work provides a new avenue for the development of efficient and stable bifunctional electrocatalysts for overall water splitting.

PANI/GO and Sm co-modified Ti/PbO2 dimensionally stable anode for highly efficient amoxicillin degradation: Performance assessment, impact parameters and degradation mechanism

The abuse and uncontrolled discharge of antibiotics present a severe threat to environment and human health, necessitating the development of efficient and sustainable treatment technology. In this work, we employ a facile one-step electrodeposition method to prepare polyaniline/graphite oxide (PANI/GO) and samarium (Sm) co-modified Ti/PbO2 (Ti/PbO2-PANI/GO-Sm) electrode for the degradation of amoxicillin (AMX). Compared with traditional Ti/PbO2 electrode, Ti/PbO2-PANI/GO-Sm electrode exhibits more excellent oxygen evolution potential (2.63 V) and longer service life (56 h). In degradation experiment, under optimized conditions (50 mg L−1 AMX, 20 mA cm−2, pH 3, 0.050 M Na2SO4, 25 °C), Ti/PbO2-PANI/GO-Sm electrode achieves remarkable removal efficiencies of 88.76% for AMX and 79.92% for chemical oxygen demand at 90 min. In addition, trapping experiment confirms that ·OH plays a major role in the degradation process. Based on theoretical calculation and liquid chromatography-mass spectrometer results, the heterocyclic portion of AMX molecule is more susceptible to ·OH attacks. Thus, this novel electrode offers a sustainable and efficient solution to address environmental challenges posed by antibiotic-contaminated wastewater.

Significantly enhanced OER and HER performance of NiCo-LDH and NiCoP under industrial water splitting conditions through Ru and Mn bimetallic co-doping strategy

High-performance electrocatalysts play a crucial role in promoting the development of industrial water splitting. Reasonable electronic structure design is key to improving the performance of electrocatalysts. This study proposed a Ru and Mn bimetallic co-doping strategy to achieve rational electronic structure design of both NiCo-LDH (RMNCL) and NiCoP (RMNCP). Specifically, we first obtained Ru and Mn bimetallic co-doped NiCo-LDH through a one-step electrodeposition, exhibiting superior catalytic activity (342 mV at 500 mA/cm2) for the oxygen evolution reaction in alkaline solution. Subsequently, we prepared Ru and Mn co-doped NiCoP by a simple phosphorization treatment of RMNCL, demonstrating impressive low overpotentials (200 mV at 500 mA/cm2) for hydrogen evolution reaction in alkaline solution. Furthermore, we constructed an anion exchange membrane electrolyzer using the prepared catalysts, achieving a high current density of 1 A/cm2 with only 2 V, maintaining stability over a prolonged 100 h duration. Further studies revealed the highly dispersed Ru atoms provided abundant active sites, while Mn modified the electron filling of anti-bonding orbitals in both catalysts, optimizing reactant adsorption. Additionally, multivalent Mn contributed to the improved catalytic performance. This study provides insights into rational electrocatalyst design and lays the foundation for catalyst development with outstanding activity under industrial-scale conditions.

Electrodeposition of CuxBi1-x-MOF for electrochemical reduction of CO2

Electrochemical reduction of carbon dioxide to hydrocarbon compounds such as formate offers a promising pathway to carbon-neutral future. Bismuth (Bi) has the advantages of low toxicity, good economic returns, and high overpotentials for hydrogen evolution reaction (HER). However, the Faradaic efficiencies and yield rates of Bi-based catalysts still need to be improved before applying to practical applications. In this work, bimetallic metal–organic framework Cux/Bi1-x-BTC was loaded on a copper foam electrode by one-step electrodeposition to form a catalytic electrode. The performance of Cux/Bi1-x-BTC electrodes for reducing carbon dioxide to formic acid was evaluated in H-type electrolytic cells. Electrochemical-prepared Cux/Bi1-x-BTC showed higher reaction rate and Faradaic efficiency (FE), than either Cu-BTC or Bi-BTC in a CO2‒saturated 0.1 M KHCO3 solution. Carbon dioxide was reduced to formic acid on CuxBi1-x-BTC electrtode. The Faradaic efficiency reached 73.4% at −1.5 V (vs. Ag/AgCl) and the conversion rate was 2.68 × 10−4 mol h−1 cm−2.

One-step electrodeposition synthesis of NiFePS on carbon cloth as self-supported electrodes for electrochemical overall water splitting

Electrocatalytic water splitting (EWS) for hydrogen production is considered an ideal strategy for utilizing renewable energy, reducing fossil fuel consumption, and addressing environmental pollution issues. Traditional noble metal electrocatalysts have excellent performance, but their cost is high. Developing efficient, stable, and relatively inexpensive dual functional electrocatalysts is crucial for promoting large-scale EWS hydrogen production processes. Herein, a simple one-step electrodeposition method was used to grow nickel–iron phosphorus-sulfides (NiFePS) on the surface of hydrophilic treated carbon cloth (CC). The resultant NiFePS/CC with a phosphorus to sulfur ratio of 1:4 exhibited the best electrocatalytic performance, requiring only −91 mV and 216 mV overpotentials to generate the current densities of 10 mA·cm−2 in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. When it was used as a bifunctional electrocatalyst to overall water splitting (OWS), a voltage of 1.536 V can generate a current density of 10 mA·cm−2. The excellent electrocatalytic performance can be ascribed to two factors: 1) the CC with excellent conductivity serves as a growth substrate, reducing the impedance of charge transfer from the electrode to the electrolyte and accelerating the electron transfer rate; 2) The large number of ultra-thin nanosheets formed on the surface of the catalyst increase the electrochemical specific surface area, expose more reaction sites, and thus improve the electrocatalytic reaction performance. This work provides a new approach for designing efficient non-noble metal electrocatalysts for water splitting.

Synergistic Effect of P and Co Dual Doping Endows CuNi with High-Performance Hydrogen Evolution Reaction.

The rational design of highly active and durable non-noble electrocatalysts for hydrogen evolution reaction (HER) is significantly important but technically challenging. Herein, a phosphor and cobalt dual doped copper-nickel alloy (P, Co-CuNi) electrocatalyst with high-efficient HER performance is prepared by one-step electrodeposition method and reported for the first time. As a result, P, Co-CuNi only requires an ultralow overpotential of 56mV to drive the current density of 10mA cm-2, with remarkable stability for over 360h, surpassing most previously reported transition metal-based materials. It is discovered that the P doping can simultaneously increase the electrical conductivity and enhance the corrosion resistance, while the introduction of Co can precisely modulate the sub-nanosheets morphology to expose more accessible active sites. Moreover, XPS, UPS, and DFT calculations reveal that the synergistic effect of different dopants can achieve the most optimal electronic structure around Cu and Ni, causing a down-shifted d-band center, which reduces the hydrogen desorption free energy of the rate-determining step (H2O + e- + H* → H2 + OH-) and consequently enhances the intrinsic activity. This work provides a new cognition toward the development of excellent activity and stability HER electrocatalysts and spurs future study for other NiCu-based alloy materials.