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Electrolysis that reduces carbon dioxide (CO 2 ) to useful chemicals can, in principle, contribute to a more sustainable and carbon-neutral future 1-6 . However, it remains challenging to develop this into a robust process because efficient conversion typically requires alkaline conditions in which CO 2 precipitates as carbonate, and this limits carbon utilization and the stability of the system 7-12 . Strategies such as physical washing, pulsed operation and the use of dipolar membranes can partially alleviate these problems but do not fully resolve them 11,13-15 . CO 2 electrolysis in acid electrolyte, where carbonate does not form, has therefore been explored as an ultimately more workable solution 16-18 . Herein we develop a proton-exchange membrane system that reduces CO 2 to formic acid at a catalyst that is derived from waste lead-acid batteries and in which a lattice carbon activation mechanism contributes. When coupling CO 2 reduction with hydrogen oxidation, formic acid is produced with over 93% Faradaic efficiency. The system is compatible with start-up/shut-down processes, achieves nearly 91% single-pass conversion efficiency for CO 2 at a current density of 600 mA cm -2 and cell voltage of 2.2 V and is shown to operate continuously for more than 5,200 h. We expect that this exceptional performance, enabled by the use of a robust and efficient catalyst, stable three-phase interface and durable membrane, will help advance the development of carbon-neutral technologies., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

A zirconium-based UiO-type UiO-66-(OH) 2 metal-organic framework@carbon dot composite (Zr-MOF@CD) is synthesized through a facile solvent-free thermal method. The Zr-MOF@CD exhibits pH-responsive fluorescence behavior, which emits blue fluorescence for pH < 9 at an emission wavelength of 470 nm. At pH > 9, the fluorescence color turns from blue to yellow, with the emission behavior at 535 nm. Zr-MOF@CDs can serve as functional nanofillers in the epoxy coating for the fabrication of a smart coating, which can realize coating damage warning and metal corrosion reporting. The blue fluorescence can be observed in the area of coating damage with just a minor scratch. Once the scratch is severe enough to expose the metal substrate, the cathodic reaction of oxygen reduction in the corrosion galvanic cell causes an increased pH, where the emission of yellow fluorescence can be identified. The stable fluorescence response is free from the influence of concentration, time, temperature, and the interfering substance. Zr-MOF@CDs can also serve as nanocontainers for loading with the corrosion inhibitor and realizing the repairing of metal corrosion. The development of the smart coating with dual functions of autonomous reporting and repairing holds great potential to improve the lifetime of metals in various industrial applications.

Biodegradable Mg and its alloys can degrade safely in vivo without toxicity. The major bottleneck inhibiting their clinical use is the high corrosion rate, which leads to the loss of mechanical integrity prematurely and bad biocompatibility. One ideal strategy is the modification with anticorrosive and bioactive coatings. Numerous metal-organic framework (MOF) membranes show satisfactory anticorrosion performance and biocompatibility. In this study, MOF-74 membranes are prepared on an NH 4 TiOF 3 (NTiF) layer-modified Mg matrix, fabricating integrated bilayer coatings (MOF-74/NTiF) for corrosion control, cytocompatibility, and antibacterial properties. The inner NTiF layer serves as the primary protection for the Mg matrix and a stable surface for the growth of MOF-74 membranes. The outer MOF-74 membranes further enhance corrosion protection, whose crystals and thicknesses can be adjusted for different protective effects. Owing to superhydrophilic, micro-nanostructural, and nontoxic decomposition products, MOF-74 membranes significantly promote cell adhesion and proliferation, showing excellent cytocompatibility. Utilizing the decomposition of MOF-74 to generate the products of Zn 2+ and 2,5-dihydroxyterephthalic acid can effectively inhibit Escherichia coli and Staphylococcus aureus , displaying highly efficient antibacterial properties. The research may shed valuable strategies for MOF-based functional coatings in the applications of biomedicine fields.

The Fructus cannabis protein extract powder (FP), was firstly used as a green and high effective corrosion inhibitor through a simple water-extraction method. The composition and surface property of FP were characterized by FTIR, LC/MS, UV, XPS, water contact angle and AFM force-curve measurements. Results indicate that FP contains multiply functional groups, such as NH, CO, CN, CO, etc. The adsorption of FP on the carbon steel surface makes it higher hydrophobicity and adhesion force. The corrosion inhibition performance of FP was researched by electrochemical impedance, polarization curve and differential capacitance curve. Moreover, the inhibitive stability of FP, and the effects of temperature and chloride ion on its inhibition property were also investigated. The above results indicate that the FP exhibits excellent corrosion inhibition efficiency (~98 %), and possesses certain long-term inhibitive stability with inhibition efficiency higher than 90 % after 240 h immersion in 1 M HCl solution. The high temperature brings about the FP desorption on the carbon steel surface, while high concentration of chloride ion facilitates the FP adsorption. The adsorption mechanism of FP follows the Langmuir isotherm adsorption. This work will provide an insight for protein as a green corrosion inhibitor., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Electrocatalysts are the core components of many sustainable energy conversion technologies that are considered the most potential solution to the worldwide energy and environmental crises. The reliability of structure and composition pledges that electrocatalysts can achieve predictable and stable performance. However, during the electrochemical reaction, electrocatalysts are influenced directly by the applied potential, the electrolyte, and the adsorption/desorption of reactive species, triggering structural and compositional corrosion, which directly affects the catalytic behaviors of electrocatalysts (performance degradation or enhancement) and invalidates the established structure-activity relationship. Therefore, it is necessary to elucidate the corrosion behavior and mechanism of electrocatalysts to formulate targeted corrosion-resistant strategies or use corrosion reconstruction synthesis techniques to guide the preparation of efficient and stable electrocatalysts. Herein, the most recent developments in electrocatalyst corrosion chemistry are outlined, including corrosion mechanisms, mitigation strategies, and corrosion syntheses/reconstructions based on typical materials and important electrocatalytic reactions. Finally, potential opportunities and challenges are also proposed to foresee the possible development in this field. It is believed that this contribution will raise more awareness regarding nanomaterial corrosion chemistry in energy technologies and beyond., (© 2022 Wiley-VCH GmbH.)

Developing facile approaches for preparing efficient electrocatalysts is of significance to promote sustainable energy technologies. Here, we report a facile iron-oxidizing bacteria corrosion approach to construct a composite electrocatalyst of nickel–iron oxyhydroxides combined with iron oxides. The obtained electrocatalyst shows improved electrocatalytic activity and stability for oxygen evolution, with an overpotential of ∼230 mV to afford the current density of 10 mA cm−2. The incorporation of iron oxides produced by iron-oxidizing bacteria corrosion optimizes the electronic structure of nickel–iron oxyhydroxide electrodes, which accounts for the decreased free energy of oxygenate generation and the improvement of OER activity. This work demonstrates a natural bacterial corrosion approach for the facile preparation of efficient electrodes for water oxidation, which may provide interesting insights in the multidisciplinary integration of innovative nanomaterials and emerging energy technologies.

Active biomass-derived carbons are brought into focus on boosting high-performance lithium storage. However, their low electric conductivity and poor ion diffusion kinetics during the lithium storage reactions remain confusing topics. This study demonstrates a novel and effective strategy of dual system activation process to construct the nitrogen-doped biomass-derived carbon with hierarchically porous architecture (HNBC), which is composed of the three-dimensional porous networks connected by carbon nanorods and the flake-like edges constructed by carbon nanosheets. A large amount of nitrogen doping can improve the conductivity and facilitate the charge transfer during charging/discharging, while the hierarchically porous structure can decrease the diffusion path for lithium-ion transport, enabling fast diffusion and charge-transfer dynamics. The HNBC electrode displays a high lithium-ion storage capacity of above 1392 mAh g -1 at 0.1 A g -1 and superior stability. Moreover, the assembled asymmetric lithium-ion capacitor exhibits excellent cycling stability and delivers a high power density of 225 W kg -1 with an energy density of 186.31 W h kg -1 . This dual system activation strategy may inspire the reasonable design of new-generation progressive carbon-based electrodes for high-performance lithium storage devices., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Nickel-iron composites are efficient in catalyzing oxygen evolution. Here, we develop a microorganism corrosion approach to construct nickel-iron hydroxides. The anaerobic sulfate-reducing bacteria, using sulfate as the electron acceptor, play a significant role in the formation of iron sulfide decorated nickel-iron hydroxides, which exhibit excellent electrocatalytic performance for oxygen evolution. Experimental and theoretical investigations suggest that the synergistic effect between oxyhydroxides and sulfide species accounts for the high activity. This microorganism corrosion strategy not only provides efficient candidate electrocatalysts but also bridges traditional corrosion engineering and emerging electrochemical energy technologies.

Pd and Pt modified N-doped titania nanoparticle powders were prepared by a facile sol-gel method. Nitrogen doping and metal modification were carried out simultaneously during the preparation pro- cess. The as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy and X-ray photoelectron spectroscopy (XPS). The visible light photocatalytic activities of the as prepared samples were evaluated by analyzing their effect on the photocatalytic decomposition of methyl orange (MO). The chemical state of the metal is the key factor determining the performance of metal modified N-doped titania. The Pd used to modify the N-doped titania (Pd-NT) in our study was of the PdOx(x≤2) species, which increased the absorbance in the visible light region, decreased the recombination of photo-generated electron-hole pairs, and resulted in a significant enhancement in the visible light photocatalytic activity. The Pt species used to modify the N-doped titania (Pt-NT) was mainly in the metallic state, which resulted in a decrease in the absorbance in the visible light region, and an increase in the recombination of photo-generated electron-hole pairs. Pt modification led to a deterioration in the visible light photocatalytic activity of the material.

The frequency domain of single channel currents is analyzed by the power distribution function (PDF) constructed by the discrete wavelet transform (DWT) and power spectral density (PSD). The result shows that the power distribution function based on DWT is an effective frequency-domain analysis method for single channel currents.