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Herein, we review the recent progress and achievements in carbon nanopore sequencing based on materials, including the selection of carbon nanomaterials, technologies for nanopore formation, and future perspectives of carbon nanopore sequencing.

Highly active, stable, and cut-price (photo-)electrocatalysts are desired to overwhelm high energy barriers for anodic oxygen evolution reaction processes. Herein, a heterostructure of cobalt-iron oxide/black phosphorus nanosheets is in-situ synthesized via a facile and novel three-electrode electrolysis method. Bulky black phosphorus is exfoliated into its nanosheets at the cathode while the CoFe oxide is derived directly from the metal wire anode during the electrolysis process. This heterostructure exhibits excellent electrocatalytic oxygen evolution reaction (OER) performance, and the overpotential at 10 mA·cm−2 is 51 mV lower than that of the commercial RuO2 catalyst. Its superior OER performance stems from the favorable adsorption behavior and an enlarged electrochemical active surface area of the catalyst. To reveal the origin of excellent OER performance from the point of adsorption strength of OH*, methanol oxidation reaction (MOR) test is applied under the identified OER operating conditions. Further introduction of light illumination enhances the OER activity of this heterostructure. The overpotential drops down to 280 mV, benefiting from pronounced photochemical response of black phosphorus nanosheets and iron oxide inside the heterostructure. This work develops a new electrochemical method to construct high performance and light-sensitive heterostructures from black phosphorus nanosheets for the OER.

Bladder cancer is the most common malignant tumours with high morbidity, mortality and recurrence. However, currently developed detection methods for bladder cancer-associated urine biomarkers are hindered by their extremely low abundance. Hence, the exploration of a highly sensitive and selective approach for the detection of trace bladder cancer-associated biomarkers in human urine is of vital importance for the diagnosis of bladder cancer. Herein, we developed a highly reliable indium gallium zinc oxide field effect transistor (IGZO FET) biosensor for the detection of bladder cancer-related biomarker microRNA. The single-stranded DNA-functionalized IGZO FET biosensors exhibit high sensing reproducibility and stability with an ultralow detection limit of 19.8 amol/L. The device could also be used for quantitative detection of trace microRNA in human urine samples and can effectively distinguish bladder cancer patients from healthy donors. The development of high performance IGZO FET biosensors presents new opportunities for the achievement of early-stage diagnosis of bladder cancer.

Design of the catalyst for efficient water dissociation and hydrogen recombination is paramount in enhancement of the alkaline water electrolysis kinetics. Herein, we reported a delicate hierarchical (VO)2P2O7-Ni2P@NF (VPO-Ni2P@NF) hybrid catalyst that operated efficiently in alkaline media. The VPO and Ni2P respectively act as the water dissociation promoter and the hydrogen recombination center, which synergistically propel water adsorption/dissociation and H intermediates recombination. The resulting synergistic interfaces between VPO and Ni2P are verified to afford the catalyst an outstanding performance for hydrogen evolution reaction in alkaline media with an overpotential of 154 mV at 10 mA cm−2, Tafel slope of 65 mV dec−1, and remarkable durability. Furthermore, the catalyst presents the potential for overall water splitting. This work may shed fresh light on the high-performance electrocatalyst design and the application of VPO on water electrolysis.

ConspectusDiamond electrodes stepped onto the stage in the early 1990s for electroanalytical applications. They possess the features of long-term chemical inertness, wide potential windows, low and stable background currents, high microstructural stability at different potentials and in different media, varied activity toward different electroactive species, reliable electrochemical response of redox systems without conventional pretreatment, high resistance to surface fouling in most cases, and possibility of forming composites with different components such as other carbon materials, carbides, and oxidizes. Most diamond electrodes are prepared in microcrystalline or nanocrystalline form using chemical vapor deposition techniques. Starting from diamond films and diamond composites, numerous nanostructured diamond electrodes have also been produced. The features of diamond electrodes are therefore heavily dependent on the growth conditions and post-treatment procures that are applied on diamond electrodes such as introduced dopant(s), surface termination(s), surface functional group(s), added components, and final structure(s). Numerous applications of diamond electrodes have been explored in the fields of electrochemical sensing, electrosynthesis, electrocatalysis, electrochemical energy storage and conversion, devices, and environmental degradation.This Account summarizes our strategies to design different diamond electrodes, including diamond films, diamond composites, as well as their nanostructures. With respect to diamond films, the modulation of their dopant(s) and surface termination(s) as well as the attachment of functional modifier(s) onto their surface are discussed. Electrochemical hydrogenation and oxygenation of diamond electrodes are detailed at an atomic scale. As the examples of designing diamond electrodes at a molecular scale, photochemical and electrochemical attachment of modifier(s) onto diamond electrodes are shown. Moreover, electrochemical grafting of diazonium salts is proposed as a new technique to identify hydrogenated, hydroxylated, and oxygenated terminations of diamond electrodes. The introduction of additional component(s) into a diamond film to form diamond composites is then overviewed, where a hydrogen-induced selective growth model is proposed to elucidate the preparation of diamond/β-SiC composites. Subsequently, the production of various diamond nanostructures from diamond films and composites by means of top-down, bottom-up, and template-free approaches is shown. Electrochemical application examples of diamond electrodes are overviewed, covering direct electrochemistry of natural Cytochrome c on a hydroxylated diamond surface, sensitive electrochemical DNA biosensing on tip-functionalized diamond nanowires, and construction of high-performance supercapacitors using diamond electrodes and redox electrolytes. Our diamond supercapacitors, also named battery-like diamond supercapacitors or diamond supercabatteries, are highlighted since they combine the features of supercapacitors and batteries. Future perspectives of diamond electrodes are outlined, ranging from their rational design and synthesis to their electrochemical applications in different fields.

A pseudocapacitive electrode with a large surface area is critical for the construction of a high-performance supercapacitor. A 3D and interconnected network composed of W

Development of sensitive, selective, and facile electrochemical analytical approaches to monitor tryptophan in different samples is of high significance. For such approaches, efficient electrodes play the key role. Herein, a NiMn-layered double hydroxide (LDH)@poly-l-lysine (PLL) composite has been prepared through in-situ electro-polymerization and further utilized to monitor tryptophan in medicament and biological systems. The as-synthesized NiMn-LDH@PLL composite is highly stable and features a flower-like morphology. It is found that the electron transfer rate of NiMn-LDH@PLL is greatly improved due to the introduction of PLL. The existing Lewis acid-base interaction between LDH and PLL contributes to the increase of unsaturated metal sites and endows this heterojunction composite with high electrocatalytic activity. Especially, the NiMn-LDH (2:1)@PLL composite displays much improved electrochemical response toward tryptophan sensing. This is due to reasonable balance between the outstanding electrocatalytic ability of nickel and the conductivity improvement caused by manganese species. On the other hand, the coordination promotion between NiMn-LDH and PLL is also conducive to improve the sensitivity of electrochemical response. The fabricated sensor exhibits wide linear response in the concentration ranges of 0.1-40 μM and 40-130 μM for tryptophan detection, along with a low detection limit of 52.7 nM. It further displays a high anti-interference ability for tryptophan monitoring even in the presence of other coexistent amino acids and small-sized biological molecules. This study provides a new way to employ LDHs as brilliant sensing platform to ensemble electrochemical sensors for the monitoring of biomolecules.

Catalysts are needed for electrochemical and photochemical reduction of CO2 into valuable chemicals. Diamond and its related materials have been regarded as a promising class of catalysts for CO2 reduction. With varied forms, structures, dopants, sp2/sp3 ratios, surface functionalities, and the combination with different co-catalysts, a great diversity of diamond-based catalysts have been fabricated for CO2 reduction. This review summarizes state-of-art progress and achievements on the electrochemical CO2 reduction using different diamond and related electrodes, along with the selection of electrolytes and applied conditions. The applications of diamond nanoparticles and diamond related films for photochemical CO2 reduction are highlighted. The advanced strategies to further improve the catalytic activity of diamond towards CO2 reduction have been discussed and outlined.

The efficient electrocatalytic degradation of environmental pollutants requires an electrode with a large surface area, high electrocatalytic activities, long-term stability, and a low cost. Herein, the diamond fibers (DFs) are synthesized by overgrowing the cost-effective carbon fibers as the core with a uniform boron dopped diamond (BDD) film as a shell. Since these fibrous core/shell-like DFs combine both features of BDD and carbon fiber, they are utilized as the electrode for the efficient electrocatalytic degradation of environmental pollutants. The DFs exhibit a 5.2-fold larger surface area and a 6.8-fold higher peak current density than those of a planar BDD electrode. Methyl orange is degraded below the limit of detection within 1.5 h using these DFs, while the degradation fraction using a planar BDD electrode is only 22%. For other various organic pollutants, these DFs exhibit excellent degradation capacity. Such a high performance of electrocatalytic degradation of these environmental pollutants originates from increased surface areas and active sites by the three-dimensional fibrous structure as well as the decreased charge-transfer resistance by the core/shell structure. These DFs are thus promising as a new electrode material or an electrocatalyst for various catalytic applications in the environmental and energy fields.

Graphite is useful as a low-cost and high-voltage cathode of dual-ion batteries (DIBs) to allow anion (de-)intercalation, yet its practical applications are hindered by low Coulombic efficiencies (...

Supercapacitors feature high power densities but low energy densities. To further improve the energy densities of supercapacitors, it is important to design and synthesize new electrode materials. ...

Flexible supercapacitors using graphene have been intensively investigated due to their potential applications for wearable and smart devices. In order to avoid stacking between graphene layers, spacers such as carbon fibers and metal oxide particles are often introduced. Such composites enhance effectively the specific surface area of the electrodes and eventually supercapacitor performance. In present work, the graphene/g-C3N4 composite is fabricated and further employed as the supercapacitor electrode. The atomic interaction between C and N of g-C3N4 and O of graphene oxide during the post-reduction in graphene oxide is found to affect device performance. The devices fabricated using the graphene/g-C3N4 composite electrode exhibit a specific area capacitance of 1500 mF cm−2, and 95% of initial capacitance after 5000 cycles and a maximum energy density of 0.075 mWh cm−2. These all-solid-state flexible supercapacitors are thus promising for miniaturized electronics.

Heavy metal ions (e.g., Cd2+ and Pb2+) are widely existed in environment and highly toxic. Their convenient, sensitive, and selective determination is thus desirable. In this study, a novel electrochemical sensing interface is developed using the composite of CeO2 nanomaterials supported on expanded graphite as the sensitive materials. As-prepared CeO2 nanomaterials through a hydrothermal method feature different morphologies (e.g., nanocube, nanopolyhedra, and nanorod-shape). Electrocatalytic ability of this interface and sensing performance towards the monitoring of Cd2+ and Pb2+ ions rely on the morphology and structure of used CeO2 nanomaterial. The interface using nanorod-shape CeO2 nanomaterials supported on expanded graphite exhibits superior electrochemical activity, namely remarkable signal enhancement for the monitoring of Cd2+ and Pb2+ ions. The developed electrochemical sensor with this r-CeO2/EG composite as the sensitive material delivers the detection limits of 0.39 and 0.21 μg L-1 for Cd2+ and Pb2+ ions, respectively.

Cubic silicon carbide (3C‐SiC) material feature a suitable bandgap and high resistance to photocorrosion. Thus, it has been emerged as a promising semiconductor for hydrogen evolution. Here, the relationship between the photoelectrochemical properties and the microstructures of different SiC materials is demonstrated. For visible‐light‐derived water splitting to hydrogen production, nanocrystalline, microcrystalline and epitaxial (001) 3C‐SiC films are applied as the photocathodes. The epitaxial 3C‐SiC film presents the highest photoelectrochemical activity for hydrogen evolution, because of its perfect (001) orientation, high phase purity, low resistance, and negative conduction band energy level. This finding offers a strategy to design SiC‐based photocathodes with superior photoelectrochemical performances., Thin films: For visible‐light‐derived water splitting to hydrogen production, nanocrystalline, microcrystalline and epitaxial (001) 3C‐SiC films are applied as photocathodes. The epitaxial 3C‐SiC film presents the highest photoelectrochemical activity for hydrogen evolution, because of its perfect (001) orientation, high phase purity, low resistance, and negative conduction band energy level.

Construction of asymmetric supercapacitors with high energy and power densities using the same anode and cathode electrodes remains a great challenge. Herein, holey reduced graphene oxide (rGO) films are synthesized using a catalytic etching process and utilized as both cathode and anode electrodes for the supercapacitor construction. On the anode of an asymmetric supercapacitor, an electrical double layer capacitor is formed in 1 M Na2SO4, while on the cathode a pseudocapacitor is fabricated where redox electrolytes of [Fe(CN)6]3-/4- are added. The performance of as-formed asymmetric supercapacitors is varied with the pore sizes and densities on the holey rGO films. With a cell voltage of 2.0 V, a specific capacitance of as high as 101.25 F g−1, an energy density of 56.25 Wh kg−1, a power density of 35.83 kW kg−1, and excellent long cycle life (98% of its specific capacitance even at 5000 charge/discharge cycles) are achieved. Such performance is superior to most of graphene based supercapacitors. Therefore, these asymmetric supercapacitors are promising for applications of storage systems with double-high densities.

Graphdiyne, a carbon allotrope, was synthesized in 2010 for the first time. It consists of two acetylene bonds between adjacent benzene rings. Graphdiyne and its composites thus exhibit ultrahigh intrinsic electrochemical activities. As "star" electrode materials, they have been utilized for various electrochemical applications. With the aim of giving a full screen of graphdiyne electrochemistry, this review starts from the history of graphdiyne materials, followed by their structural and electrochemical features. Recent progress and achievements in the synthesis of graphdiyne materials and their composites are overviewed. Subsequently, various electrochemical applications of graphdiyne materials and their composites are summarized, covering those in the fields of electrochemical energy conversion, electrochemical energy storage, and electrochemical sensing. The perspectives of graphdiyne electrochemistry are also discussed and outlined.

Constructing ionic conductive hydrogels with diversified properties is crucial for portable zinc-ion hybrid supercapacitors (ZHSCs). Herein, a freeze-tolerant hydrogel electrolyte (AF PVA-CMC/Zn(CF

The properties and applications of metal-organic frameworks (MOFs) can be tuned by their metal centers and organic ligands. To reveal experimentally and theoretically the influence of metal centers and ligands on electrochemical performance of MOFs, three MOFs with copper or zinc centers and organic ligands of 2-methylimidazole (2MI) or 1,3,5-benzenetricarboxylic acid (H

Rechargeable aqueous zinc-ion hybrid capacitors (ZHCs) have aroused unprecedented attention because of their high safety, cost effectiveness, and environmental compatibility. However, the intractable issues of dendrite growth and side reactions at the electrode-electrolyte interface deteriorate durability and reversibility of Zn anodes, deeply encumbering the large-scale application of ZHCs. Concerning these obstacles, a negatively charged carboxylated chitosan-intensified hydrogel electrolyte (CGPPHE) with cross-linked networks is reported to stabilize Zn anodes. Beyond possessing good mechanical characteristics, the CGPPHE with polar groups can reduce the desolvation energy barrier of hydrated Zn