Catalytic Activity In Reaction Research Articles

Cobalt Incorporation Promotes CO2 Desorption from Nickel Active Sites Encapsulated by Nitrogen-Doped Carbon Nanotubes in Urea-Assisted Water Electrolysis.

The potential application prospects of urea-assisted water electrolysis toward hydrogen production in renewable energy infrastructure can effectively alleviate energy shortages and environmental pollution caused by rich urea wastewater. It is of prominent significance that adjusting the CO2 desorption of nickel-based electrocatalysts can overcome the slow reaction kinetics for urea oxidation reaction (UOR) to achieve exceptional catalytic activity. In this work, cobalt (Co) metal doping is employed to boost the UOR performance of nitrogen-doped carbon nanotubes encapsulating nickel nanoparticle electrocatalysts (Ni@N-CNT). The influence of diverse Co doping concentrations on the performance of UOR and hydrogen evolution reaction (HER) catalytic activities associated with stability are systematically investigated. The Co dopant can effectively promote the dynamical conversion of Ni to Ni3+ species; as a result, the UOR catalytic activity is improved by 1.8-fold at 1.6 V vs RHE. The DFT calculation results show that the CoNi bimetallic structure possesses a comparably lower binding energy for CO2 adsorption accelerating the rate-limiting step. Meanwhile, the Co dopant also boosts the HER performance, achieving a 57 mV reduction in overpotential at 100 mA cm-2 due to the creation of more active sites. In addition, the assembled urea-assisted water electrolysis attains 10 mA cm-2 at merely 1.51 V as well as excellent stability.

Density Functional Theory Study on Screening and Key Metrics for Non-metallic Oxygen Reduction Catalysts.

This study systematically investigates the oxygen reduction reaction (ORR) catalytic activity of graphene doped with various non-metallic impurities. The non-metal elements include boron (B), silicon (Si), nitrogen (N), phosphorus (P), arsenic (As), oxygen (O), sulfur (S), selenium (Se), tellurium (Te), fluorine (F), chlorine (Cl), bromine (Br), and iodine (I). We found that adsorbates tend to adsorb on positively charged impurity atoms. We identified several substrates with good catalytic activity, all of which have an ORR overpotential of around 0.6 V. We further verified the thermodynamic stability of these substrates and found them to be very stable. We summarized the optimal adsorption energies for ORR intermediates O2H, O, and OH to be -1.9, -3.4, and -2.4 eV, respectively, and validated their reasonableness. Finally, we used simple linear functions to fit the relationship between the adsorption energies of O2H, O, and OH and the charge and magnetic moment of the adsorption site atoms. This model can roughly predict the ORR catalytic activity of doped graphene, facilitating the faster screening of excellent ORR catalysts.

Peptide-Functionalized Gold Nanoparticles as Organocatalysts for Asymmetric Aldol Reactions

The use of high catalyst loading is required for most of the organocatalyzed asymmetric aldol reactions in organic synthesis, and this often presents challenges during purification and difficulties in catalyst recovery from the reaction mixture. The immobilization of the catalyst onto gold nanoparticles (AuNPs) can change the structural conformations of the catalyst, thereby improving its catalytic activity and reusability. Herein we report on the synthesis of aldolase mimetic peptide coupled to gold nanoparticles (AuNPs) as efficient organocatalysts for asymmetric aldol reaction. AuNPs were synthesized using the Turkevich method. The conjugation of the peptide to AuNPs was characterized using surface plasmon resonance (SPR), Raman and X-ray photoelectron spectroscopy, and transmission electron microscopy (TEM) was used for particle size determination. The produced nanoparticles, whose sizes depended on the reduction method, were quasi-spherical with a relatively narrow size distribution. The peptide–AuNP conjugates were evaluated for aldol reaction catalytic activity between carbonyls p-nitrobenzaldehyde and cyclohexanone. The products were obtained with good yields (up to 85%) and enantioselectivity (up to 94%). The influence of organic solvents, pH and buffer solutions was also investigated. The results showed that the buffer solutions regulated the colloidal stability of AuNPs, resulting in a significant enhancement in the catalytic rate of the peptide–AuNP conjugate.

Enhancing Oxygen Reduction Reaction Electrocatalytic Performance of Nickel‐Nitrogen‐Carbon Catalysts through Coordination Environment Engineering†

Comprehensive SummarySingle‐atom catalysts (SACs) have attracted significant attention due to their high atomic utilization and tunable coordination environment. However, the catalytic mechanisms related to the active center and coordination environment remain unclear. In this study, we systematically investigated the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) catalytic activities of NiN4, NiN3, NiN3H2, NiN4X, NiN3X, and NiN3H2X (X denotes axial ligand) through density functional theory (DFT) calculations. This study unveils two distinct reaction pathways for ORR and OER, involving proton‐electron pairs adsorbed from both the solution and the catalyst surface. The overpotential is the key parameter to evaluate the catalytic performance when proton‐electron pairs are adsorbed from the solution. NiN3 and NiN3H2 show promise as pH‐universal bifunctional electrocatalysts for both ORR and OER. On the other hand, when proton‐electron pairs are adsorbed from the catalyst surface, the reaction energy barrier becomes the crucial metric for assessing catalytic activity. Our investigation reveals that NiN3H2 consistently exhibits optimal ORR activity across a wide pH range, regardless of the source of proton‐electron pair (solvent or catalyst surface).

Atomic catalysis meets heterostructure synergy: Unveiling the trifunctional efficacy of transition Metal@WS2/ReSe2

Integrating and advancing renewable energy storage and conversion technologies such as water splitting and rechargeable air-based batteries face significant challenges in finding appropriate catalysts that offer both high activity and low cost. This paper successfully designed efficient, cost-effective, and eco-friendly catalysts that meet the requirements for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) catalytic activity by employing two-dimensional (2D) transition metal dichalcogenides (TMDs) interface engineering combined with a single-atom doping strategy. First, the heterostructure was constructed, and its optimal layer spacing (3.13 Å) was determined by calculating the most negative binding energy. These materials were theoretically evaluated using density functional theory (DFT), demonstrating that transition metal (TM) can all be firmly attached to the S1 site of the WS2/ReSe2 Z-scheme heterostructure with favorable binding energies and excellent electronic properties. By comparing the catalysts doped with different metals (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn), the three functional catalysts with the best performance were finally selected: Mn@WS2/ReSe2, Ni@WS2/ReSe2, and Cu@WS2/ReSe2. In particular, Mn@WS2/ReSe2 exhibited exceptional promise as multifunctional catalysts, with overpotentials for the HER/OER/ORR of 0.05/0.29/0.35 V, respectively. The superior catalytic performance of this WS2/ReSe2 Z-scheme heterostructure was attributed to the introduction of TM atoms and the synergistic interaction between rhenium and the TM atoms. This interaction facilitated more efficient electron transfer between the catalyst and the reactants, enhancing the overall catalytic activity. This research is a successful attempt to combine interface engineering with single-atom catalysis (SACs). It provided valuable insights into the design of next-generation multifunctional electrocatalysts, offering a novel approach to address the growing energy demands in an environmentally benign and economically viable way.

Temperature-controlled in-situ construction of composition-tunable nanoparticle-decorated SOFC cathodes with enhanced oxygen reduction kinetics and CO2 tolerance

High oxygen reduction reaction (ORR) catalytic activity and CO2 resistance of the cathode are fundamental to the commercial application of solid oxide fuel cells (SOFCs). Therefore, we develop a temperature-driven reduction-reoxidation strategy to in-situ construct heterostructured perovskite cathodes decorated with different nanoparticles by controlling the reduction temperature. For (Pr0.4Sr0.6)0.95Co0.2Fe0.8-xNixO3-δ (PSCFN, x = 0.05, 0.1), reduction (@700 °C)-reoxidation results in the exsolution of a ComFenNi3-m-nO4 spinel phase on the perovskite scaffold surface, while reduction (@750 °C)-reoxidation leads to the formation of both ComFenNi3-m-nO4 spinel phase and NiO nanoparticles. The exsolution of these highly active species increases the quantity of oxygen reduction active sites and effectively suppresses Sr segregation. The simultaneous formation of ComFenNi3-m-nO4 spinel phase and NiO nanoparticles induces B-site ion vacancies in the main phase, therefore facilitates the formation of oxygen vacancies. Additionally, the presence of ComFenNi3-m-nO4/NiO/PSCFN heterointerfaces promotes oxygen adsorption and transfer. The strong interactions among ComFenNi3-m-nO4, NiO, and PSCFN significantly enhance the structural stability. At 800 °C, Reo2-PSCFN0.1 achieves an output performance of 1.12 W cm−2, representing a 36.6 % enhancement compared to PSCFN0.1. Moreover, the Rp of Reo2-PSCFN0.1 is merely 0.0186 Ω cm2, marking a 40.4 % decrease relative to PSCFN0.1. This temperature-driven reduction-reoxidation strategy shows great promise as a novel approach for creating high-performance IT-SOFC cathodes.

CoFe2O4 with the In-Situ Formed Oxygen Vacancies and Co Particles as an Efficient Bifunctional Catalyst for Rechargeable Zinc-Air Batteries.

Rechargeable zinc-air batteries (RZABs) are considered as one of the most promising clean energy device due to their abundant resources, low cost and environmental friendliness. However, their energy efficiency and cycle life are far from satisfactory due to the poor activity and stability of bi-functional electrocatalyst in air cathode. In this work, an efficient bi-functional catalyst (rGO-CoFe2O4/Co) was derived from its precursor (rGO-CoFe2O4) through a simple annealing process. Electrochemical measurements prove that rGO-CoFe2O4/Co with the in-situ formed Co nano particles and rich oxygen vacancies appears excellent oxygen reduction reaction and oxygen evolution reaction catalytic activity compared to its counterpart. Its half-wave potential is 0.81 V (vs RHE) and the OER overpotential is only 310 mV (vs RHE). In addition, rechargeable zinc-air batteries assembled with rGO-CoFe2O4/Co show the highest peak power density (128.9 mW cm-2) and cycling stability compared to rGO-CoFe2O4 and commercial Pt/C-RuO2 catalysts. This work provides a simple strategy for the design of advanced bifunctional catalysts.

The Construction of Face-to-Face Combination between NiFe-layered Double Hydroxide Nanosheets and Monolayer rGO for Efficient Water Splitting and Oxygen Reduction.

Developing cost-effective and efficient electrocatalysts is essential for advancing a green energy future. Herein, a NiFe-layered double hydroxide loaded on reduced graphene oxide (NiFe-LDHs@rGO) hybrid was synthesized using a straightforward three-step process involving exfoliation tearing, electrostatic self-assembly, and chemical reduction. The face-to-face packing and ultrathin exfoliation enable strong heterogeneous interactions, fully harnessing the potential of these complementary two-dimensional counterparts. Consequently, the resultant catalyst displays outstanding oxygen evolution reaction (OER) catalytic activity and stability, whose overpotential is as low as 241 mV at 30 mA cm-2 and 255 mV at 50 mA cm-2 with a low Tafel slope of 62.1 mV dec-1. Both the experimental results and density functional theory (DFT) calculations reveal that the face-to-face assembly strengthens the electronic interactions between NiFe-LDHs and rGO, which effectively modulates the d-band center of Ni and Fesites and improves the reaction kinetics for OER. Moreover, the resultant NiFe-LDHs@rGO hybrids exhibit excellent multifunctional catalytic performance. Its hydrogen evolution reaction (HER) activity is endowed by Fe-site of NiFe-LDHs and defect states rGO and achieves a low voltage of 1.68 V to drive a current density of 10 mA cm-2 for overall water splitting. The face-to-face heteroassembly also imparts NiFe-LDHs@rGO with superior oxygen reduction reaction (ORR) activity, with a half-wave potential of 0.70 V and a limiting current density of 4.2 mA cm-2. Its ORR primarily follows a four-electron transfer pathway with a minor contribution from a two-electron process. This study establishes the groundwork for optimizing two-dimensional heterogeneous interfaces in LDH@carbon-based materials for advanced energy conversion.

Controlled synthesis of the M doped (M = Fe, Cu, Zn, Mn)-Co4S3/Ni3S2 catalyst with high electrocatalytic performance for hydrogen evolution reaction in seawater and urea

Electrolysis of seawater is a promising method for producing hydrogen, but sluggish reaction kinetics and electrolyte containing corrosive ions limit its development. In this work, a series of M doped (M = Fe, Cu, Zn, Mn)-Co4S3/Ni3S2 catalyst has been prepared on Ni foam by hydrothermal method with excellent seawater and urea splitting performance. The unique 3D porous structure provides a large number of active sites for the catalyst, which has strong catalytic activity. Fe-Co4S3/Ni3S2 electrode showed excellent hydrogen evolution reaction (HER) catalytic activity in 1 M KOH + seawater and 1 M KOH + 0.5 M urea, driving a current density of 10 mA cm−2 at a low overpotential of 81 and 66 mV. In addition, Fe-Co4S3/Ni3S2 electrode also shows strong stability in 15 h stability test. The results show that although the impurity ions in seawater affect the activity of catalyst, the corrosion resistance of catalyst also improves the catalytic activity and stability. Density functional theory calculations show that this Fe-Co4S material exhibits the optimal Gibbs free energy of hydrogen, the introduction of this Ni3S2 material enhances the electrical conductivity of the material, and the synergistic catalysis of the two materials promotes the optimal hydrogen production performance of the Fe-Co4S3/Ni3S2 material. This work provides a novel understanding for the research of catalysts used in the electrolysis of seawater and urea.

WN-CoS2 nanoparticles encapsulated into carbon nanotubes enable a stable and high-performance rechargeable zinc air battery

The battery performance associated with longevity are the priorities for the industrialization of rechargeable zinc air battery (ZAB). Herein, we have reported the construction of WN-CoS2 heterostructure enveloped by nitrogen and phosphorus co-doped carbon nanotubes (WN-CoS2@NPCNT). WN-CoS2@NPCNT performs a superior oxygen evolution reaction (OER) catalytic activity of 279 mV overpotential to reach 10 mA cm−2, lowered by 85 mV with relative to CoS2@NCNT attributing to the heterostructure efficiently modulating the electronic structure of active sites. Besides, the half-wave potential reaches 0.875 V vs. RHE for WN-CoS2@NPCNT under oxygen reduction reaction (ORR) condition, corresponding to a 3.2-time higher kinetic current density compared to commercial Pt/C. Due to the exceptional bifunctionality, the battery performance is 205 mW cm−2 for WN-CoS2@NPCNT, 1.54 times higher than commercial counterpart, Pt/C + IrO2. Impressively, the battery performance sustains for 1000 h for WN-CoS2@NPCNT stemming from the confinement effect caused by NPCNT. In addition, the all-solid-state ZAB shows a high-power density of 55 mW cm−2.

Construction of high‐loading WO3‐x sub‐nanometer clusters via orderly‐anchored top–down strategy boost acidic hydrogen evolution

AbstractExploring a simple, rapid, and scalable synthesis method for the synthesis of high loading nonprecious metal sub‐nanometer clusters (SNCs) electrocatalysts is one of the most promising endeavors today. Herein, an orderly‐anchored top–down strategy is proposed for fabricating a new type of high loading WO3‐x SNCs on O‐functional group‐modified Ketjen black (WO3‐x‐C(O)) to balance the high loading (49.29 wt.%) and sub‐nanometer size. By optimizing the vacancy number, WO2.71‐C(O) has extremely large electrochemically active surface area (402 m2 g−1) and high turnover frequency value of 1.722 s−1 at −50 mV (vs. reversible hydrogen electrode). The overpotential of WO2.71‐C(O) reaches 22 mV at a current density of 10 mA cm−2, which is significantly better than the commercial Pt/C level (32 mV), achieving a breakthrough in the hydrogen evolution reaction (HER) catalytic activity of nonprecious metals in acidic environment. Theoretical calculations and in situ characterization show that this material allows for the enrichment of reactants (H*) and the optimization of intermediate adsorption, which leads to the enhancement of acidic HER catalytic activity.

High-Throughput screening of TM1TM2/N6–1 (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Mo) as effective electrocatalysts for nitrogen fixation

The electrochemical nitrogen reduction reaction (NRR) is an emerging nitrogen fixation method in recent years. Double-atom catalysts compensate for the disadvantage of single-atom catalysts having only one active site, improving catalytic reaction activity. Herein, using a four-step high-throughput screening strategy with density functional theory (DFT) calculations, 45 homonuclear and heteronuclear catalysts, namely, transition metal dimers anchored on nitrogen-doped graphene (TM1TM2/N6–1, TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Mo), were systematically studied to evaluate their catalytic performance for NRR. Our results showed that 16 catalysts stand out, among them, ScMo/N6–1 has an ultralow limiting potential of -0.09 V and a Faradaic efficiency of 100 %. This work provides a group of promising candidates and a reasonable high-throughput design strategy for NRR catalysts.

RETRACTED: Fe–Co co-doped 1D@2D carbon-based composite as an efficient catalyst for Zn-air batteries

A Fe-Co dual-metal co-doped nitrogen-containing carbon composite (FeCo-HNC) was prepared by adjusting the ratio of iron to cobalt as well as the pyrolysis temperature with the assistance of functionalized silica template. Fe1Co-HNC, which was made from 1D carbon nanotubes and 2D carbon nanosheets with a rich mesoporous structure, presented exceptional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic activity. The ORR half-wave potential is 0.86 V (vs. reversible hydrogen electrode, RHE), and the OER overpotential is 0.76 V at 10 mA cm−2 with the Fe1Co-HNC catalyst, which can be applied to zinc-air batteries with superior performance. It is worth noting that the zinc-air batteries with Fe1Co-HNC-1000 as the cathodic catalyst achieved the highest power density of 94.9 mW cm−2 under a current density of 159.8 mA cm−2. This method provides a promising strategy for fabricating efficient transition metal-based carbon catalysts.

Self-assembled formation of platinum single atoms and nanoclusters stabilized on MXene as an efficient catalyst for boosting electrocatalytic hydrogen evolution

Atomic isolated and dispersed single atom catalyst is ideal for high-performance industrial catalyst. However, the contribution from small amounts of nanoclusters coexisting with single atoms to the catalytic reaction activity is often neglected. In this work, a MXene-supported uniformly dispersed Pt single atoms and nanoclusters (Pt1+Ptn/MXene) were obtained by self-assembly through an impregnation method. The catalyst exhibits high electrochemical performance in the hydrogen evolution reaction with an overpotential of only 61.3 mV and a Tafel slope of 32.5 mV dec−1 at a current density of 10 mA cm−2 in an acidic environment. The XAFS analysis and further DFT calculation indicate that the synergistic effect between single atoms and nanoclusters can facilitate adsorption of H* and promote the HER reaction. This work provides an efficient method for integrating multiple active sites in noble metal catalysts.

Ru-Mn pair-site triggers key oxygen intermediate for enhanced acidic oxygen evolution reaction kinetics

Charge and spin regulation of electrons are identified as a vital factor in improving the oxygen evolution reaction (OER) catalytic activity. Nevertheless, the influence of surface reconstruction on charge and spin structure under complex catalytic reaction conditions has been unintentionally neglected. Correct understanding and targeted regulation of surface reconstruction are the key to prepare high active catalysts. Herein, variable valence states Mn is adopted to regulate Ru-NC, which serves as a model to reduce the localization of Ru 4d structure and stimulate facile charge transfer, achieving accelerated surface reconstruction to generate Ru-O active ingredient with high active to acidic water oxidation. Doping Mn not only accelerates surface reconstruction, but also improves durability by eliminating Ru peroxidation due to Mn-buffered charge compensation. The enhancement of OER activity results from the Mn and O induced Ru spin states to change from intermediate spin to low spin, thereby weakening the interaction with *O intermediates, and promoting *OH adsorption, which benefits the initial step of OER. This study not only provides a strategy to achieve directional reconstruction with the help of metal site asymmetry, but also provides a thorough comprehension of charge and spin dependent acidic OER kinetics.

Phosphorus and nitrogen co-doped-graphene: Stability and catalytic activity in oxygen reduction reaction

This study systematically investigated the stable configurations and oxygen reduction reaction (ORR) catalytic activity of PN co-doped graphene using first-principles methods. We found that PN co-doped graphene substrates are generally highly stable. The adsorption energy of adsorbates is linearly positively correlated with the number of electrons obtained from the substrate. The P atoms serve as catalytic activity sites, the co-doping of N significantly enhances the adsorption energies of intermediate species in the ORR process, facilitating the direct dissociation of O2 and O2H. The solvation effect has a non-negligible impact on the adsorption energy of adsorbates, especially for O2. Due to the excessive adsorption of O, it poisons and inhibits the catalytic activity of P active sites for ORR. However, after O adsorption, the C atoms neighboring the PN impurity atoms in the P-Nn-Gra (n=2,3) substrates exhibit better catalytic activity than that of graphene doped with P/N alone. The P-Nn-defect-Gra (n=2,3,4) substrates are potential catalysts with good HER catalytic activity.

Hydrophobic Microenvironment Modulation of Ru Nanoparticles in Metal-Organic Frameworks for Enhanced Electrocatalytic N2 Reduction.

The modulation of the chemical microenvironment surrounding metal nanoparticles (NPs) is an effective means to enhance the selectivity and activity of catalytic reactions. Herein, a post-synthetic modification strategy is developed to modulate the hydrophobic microenvironment of Ru nanoparticles encapsulated in a metal-organic framework (MOF), MIP-206, namely Ru@MIP-Fx (where x represents perfluoroalkyl chain lengths of 3, 5, 7, 11, and 15), in order to systematically explore the effect of the hydrophobic microenvironment on the electrocatalytic activity. The increase of perfluoroalkyl chain length can gradually enhance the hydrophobicity of the catalyst, which effectively suppresses the competitive hydrogen evolution reaction (HER). Moreover, the electrocatalytic production rate of ammonia and the corresponding Faraday efficiency display a volcano-like pattern with increasing hydrophobicity, with Ru@MIP-F7 showing the highest activity. Theoretical calculations and experiments jointly show that modification of perfluoroalkyl chains of different lengths on MIP-206 modulates the electronic state of Ru nanoparticles and reduces the rate-determining step for the formation of the key intermediate of N2H2 *, leading to superior electrocatalytic performance.

Template-Assisted in situ synthesis of superaerophobic bimetallic MOF composites with tunable morphology for boosted oxygen evolution reaction

CoFe bimetallic organic frameworks (CoFe-MOFs) with tunable morphology and electronic structure are synthesized in situ utilizing cobalt hydroxide (Co(OH)2) as a semi-sacrificial template and different anionic iron salts as modifying factors in a non-calcined synthesis method. This work defines the impact of three different anionic metallic iron salts (FeCl3, Fe(NO3)3, and Fe2(SO4)3) on the morphology of MOF materials and their resulting oxygen evolution reaction (OER) catalytic activity. Employing ferric chloride (FeCl3) as the metallic iron source, heterostructured electrocatalysts (BN-CoFe-MOF) with nanoparticles decorated nanoneedle tips are obtained, exhibiting a low overpotential (230 mV at 10 mA cm−2) and a Tafel slope of 105.6 mV dec−1 in 1.0 M KOH. It also demonstrates long time stability for at least 50 h at a current density of 10 mA cm−2. The investigation uncovers that the splendid OER activity and stability of the BN-CoFe-MOF heterojunction can be attributed to its large specific surface area, desirable mesoporous structure, superaerophobic characteristic, and high exposure of active centers. This work not only provides an efficient and cost-effective MOF based OER electrocatalyst but also serves as a valuable reference for future research on morphology control and strategies to enhance the OER activity of MOF catalysts.

Mxene-based capacitive enzyme-free biofuel cell Self-Powered sensor for lead ion detection in human plasma

In response to the health risks posed by heavy metal lead, we have developed a self-powered sensor specifically designed for detection of lead ions in this work. This sensor is designed based on an enzyme-free biofuel cell as a self-powered source. The biofuel cell utilizes two-dimensional lamellar Au NPs-Ti3C2Tx heterostructures as the capacitive anode substrate material. The Ti3C2Tx MXene with the excellent charge storage capacity and fast discharge characteristics, provides a large instantaneous current for signal amplification. Furthermore, the DNA walker technique was combined to regulate the loading of ultra-small Au NPs exhibiting glucose oxidase-like properties. Meanwhile, Co, Mn nitrogen-doped carbon-based nanosheets were designed as the cathode with outstanding oxygen reduction reaction catalytic activity. As a result, the constructed enzyme-free biofuel cell has been used to detect Pb2+ with a wide linear range (0.01–7500 nM) and a low detection limit (0.43 pM). It has been successfully applied to the determination of Pb2+ in human plasma, achieving excellent recovery rates (94.0–110.5 %). The developed capacitive anodes not only significantly optimized the performance of the biofuel cell self-powered sensors, but also provided important insights for the future design and construction of biofuel cells.

3D transition metal boride monolithic electrode for industrial hectoampere-level current anion exchange membrane water electrolysis

High performance, cost-efficient anion exchange membrane water electrolysis (AEMWE) is of great current interest for industrial-level hydrogen production. However, the lack of active and robust catalytic electrode severely impedes the development of this technology. Herein, a versatile strategy of 3D hierarchical porous monolithic electrode enabling industrial hectoampere-level current AEMWE is successfully explored for the first time. By a facile electroless plating technique coupled with corrosion engineering process, a series of low-cost and highly active 3D transition metal boride (etched-TMB, TM=Ni, Co, NiP, NiMo, CoP, CoMo, CoNi) catalytic electrodes have been prepared. A distinctive hierarchically structured etched-NiPB@MS alloy monolithic electrode exhibits a superior bifunctional hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalytic activity and large-current stability, which derive from enhanced intrinsic activity, sufficient electrochemical active sites, mechanical stability as well as efficient gas/liquid transport pathways. An AEMWE electrolyzer with 10×10 cm2 etched-NiPB@MS as both anode and cathode works efficiently at large current of 100 A (1 A cm−2) and reaches a H2 production rate of 41.78 L h−1, verifying its huge potential for industrial hydrogen production. This study paves out a new approach for high-efficient catalytic electrode and industrial-level current AEMWE.