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Metal sulfides are commonly used in energy storage and electrocatalysts due to their redox centers and active sites. Most literature reports show that their performance decreases significantly caused by oxidation in alkaline electrolyte during electrochemical testing. Herein, S and N co‐doped graphene‐based nickel cobalt sulfide aerogels are synthesized for use as rechargeable alkaline battery electrodes and oxygen reduction reaction (ORR) catalysts. Notably, this system shows improved cyclability due to the stabilization effect of the S and N co‐doped graphene aerogel (SNGA). This reduces the rate of oxidation and the decay of electronic conductivity of the metal sulfides materials in alkaline electrolyte, i.e., the capacity decrease of CoNi2S4/SNGA is 4.2% for 10 000 cycles in a three‐electrode test; the current retention of 88.6% for CoS/SNGA after 12 000 s current–time chronoamperometric response in the ORR test is higher than corresponding CoS nanoparticles and CoS/non‐doped graphene aerogels. Importantly, the results here confirm that the NiCoS ternary materials behave as an electrode for rechargeable alkaline batteries rather than supercapacitors electrodes in three‐electrode test as commonly described and accepted in the literature. Furthermore, formulas to evaluate the performance of hybrid battery devices are specified.

Nanostructures of metal oxide semiconductors play significant roles in a variety of areas, such as biotherapy, pollutant treatment and energy storage and conversion. The molybdenum oxide (MoO3−x) nanostructures have shown promising applications especially when used as photothermal treatment agents due to their relatively low cost, facile synthesis and low toxicity. However, the design and synthesis of efficient MoO3−x nanomaterials with tunable phases and morphologies for theragnosis of tumors remains a challenge. In this work, hydrophilic MoO3−x with controlled structures and phases was synthesized by a simple one-step hydrothermal process. The as-obtained MoO2 nanoclusters showed a desirable size of ∼40 nm in diameter exhibiting unique properties as a theragnosis nanoplatform: (1) strong near-infrared absorption, which is due to oxygen vacancies of the nanoclusters, as proved by photoluminescence spectroscopy and X-ray photoelectron spectroscopy; (2) excellent photothermal performance with a photothermal conversion efficiency of up to 62.1%; and (3) the image response of X-ray computed tomography (CT) and infrared thermal imaging for simultaneous diagnosis of tumors. This study provided the facile synthetic strategy for controllable metal oxide semiconductors and promoted the development of metal oxides for theragnosis therapy of cancers.

Limited by the relatively low adsorption capacity of inorganic nanomaterials for antibiotics , ultralong hydrogen titanate nanobelts (UHTNs) with a hollow structure and high surface area (442.21 m2 g−1) were synthesized to evaluate the feasibility as a potential adsorbent material for antibiotic removal. A batch of adsorption experiments were conducted by using norfloxacin (NFO), tetracycline (TC) and ofloxacin (OFO) as the model antibiotic molecules. The results indicate that the adsorption of antibiotics on UHTNs is better fitted to the pseudo-second-order kinetic model, and the UHTNs' maximum adsorption capacities calculated from the Langmuir isotherm model were 151.51 mg g−1 for TC, 111.73 mg g−1 for NFO, and 148.14 mg g−1 for OFO at pH = 7, which are far better than those of most reported inorganic adsorbent materials. In the adsorption process of tetracycline, the surface complexation between the adsorbent and TC contributed most to the adsorption; this has been elucidated by Fourier Transform Infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). In addition, because the UHTNs are up to tens of micrometers in length, they can be easily aggregated to form a network. Therefore, a novel paper-like, free-standing UHTN membrane was fabricated via a simple vacuum filtration method, which also exhibits good adsorption capacity.

Durable non-wetting surfaces require high surface roughness on the nano- or micrometer scale, which is inherently fragile and easily removed by an external force. Elastic materials have potential advantages for constructing superhydrophobic surfaces with abrasion resistance since after friction or force deformation they often rebound to their original structure rather than undergoing degradation. Here we present a large-scale fabrication of free-standing silicone monoliths with a stable Cassie–Baxter state under mechanical stress cycles. The obtained elastic silicone retains excellent mechanical durability with constant super liquid-repellent after high external pressure, knife-scratch, and abrasion cycles with sandpaper. Furthermore the obtained silicone demonstrates high tolerance to continuous contact with extremely corrosive solutions, and also shows self-cleaning properties in air or under oil.

In this work, we report a facile one-step hydrothermal approach to synthesize NiWO4 and CoWO4 nanostructures on nickel foam as binder-free electrodes for use as supercapacitors. The as-synthesized materials showed excellent electrochemical performance, with a high specific capacitance of 797.8 F g−1 and 764.4 F g−1 at a current density of 1 A g−1 after 3000 cycles. On increasing the current density by 20 times, the rate capabilities still maintained 55.6% and 50.6% of the original value for NiWO4/Ni foam and CoWO4/Ni foam, respectively. Moreover, both of these materials exhibited outstanding cycling stability, the 6000th cycle at 50 mV s−1 demonstrated 2.06 and 2.81 times better capacitance than the initial cycles for NiWO4/Ni foam and CoWO4/Ni foam, respectively. To our knowledge, this capacitance performance is better than any previously reported value for these materials and is a consequence of the highly evolved surface area/microstructure of the materials formed by this technique.

Many advanced materials are designed for separation of immiscible oils/organic solvents and aqueous solutions, including poly(vinylidene fluoride) (PVDF)‐based materials with superwettability. However, due to the limited solubility of PVDF, techniques (e.g., phase inversion and electrospinning) often involve the use of toxic organic solvents. Here a facile organic solvent‐free method is described to prepare a porous PVDF–MWCNT (multiwalled carbon nanotube) foam using table salt as a sacrificial template. The porous PVDF–MWCNT foam is characterized as superhydrophobic–superoleophilic with good elasticity due to its 3D porosity and low surface energy. The foam exhibits high adsorption capacity to a variety of oils/organic solvents and can be easily reused by squeezing, heating, or releasing in other solvents. Moreover, the foam is highly resistant toward UV exposure, corrosive aqueous solutions such as acidic, alkaline, salty solutions, and turbulent environments, and shows effective oils/organic solvents removal in these complex environments. The continuous separation of immiscible oils/organic solvents and corrosive aqueous solutions with vacuum assistance is also presented. The organic solvent‐free and reusable PVDF–MWCNT foam is a promising candidate for large‐scale industrial separation of oils/organic solvents and water in corrosive and turbulent conditions.

A uniform dendritic NiCo2S4@NiCo2S4 hierarchical nanostructure of width ≈100 nm is successfully designed and synthesized. From kinetic analysis of the electrochemical reactions, those electrodes function in rechargeable alkaline batteries (RABs). The dendritic structure exhibited by the electrodes has a high discharge‐specific capacity of 4.43 mAh cm−2 at a high current density of 240 mA cm−2 with a good rate capability of 70.1% after increasing the current densities from 40 to 240 mA cm−2. At low scan rate of 0.5 mV s−1 in cyclic voltammetry test, the semidiffusion controlled electrochemical reaction contributes ≈92% of the total capacity, this value decreases to ≈43% at a high scan rate of 20 mV s−1. These results enable a detailed analysis of the reaction mechanism for RABs and suggest design concepts for new electrode materials.

Graphitic carbon nitride (g-C3N4) contains a high C/N ratio of 3/4; however, utilizing nitrogen atoms in pseudocapacitive energy storage systems remains a challenge due to the limited number of edge nitrogen atoms and inherent poor electrical conductivity of this semi-conductor material. 3D oxidized g-C3N4 functionalized graphene composites (GOOCN24), in which reduced graphene oxide providing high electron conductivity acts as a skeleton and hybridises with oxidized g-C3N4 segments, were synthesized using a facile two-step solution-based method. Due to the pre-oxidation treatment of g-C3N4, which breaks the polymeric nature of g-C3N4 and increases in the proportion of edge nitrogen atoms and the subsequent solubility in water, the GOOCN24 composites used as electrodes for supercapacitors show a specific capacitance as high as 265.6 F g−1 in acid electrolyte and 243.8 F g−1 in alkaline electrolyte in three-electrode configuration at a current density of 1 A g−1. In addition, low internal resistance, excellent rate performance of over 74% capacitance retention (over a 50-fold increase in current density), and outstanding cycling stability of over 94% capacitance retention after 5000 cyclic voltammetry cycles in both alkaline and acid electrolytes was attained. This translated into excellent energy density with appropriate power density when demonstrated in a symmetrical device.

Nanostructured V2O5 is emerging as a new cathode material for lithium ion batteries for its distinctly high theoretic capacity over the current commercial cathodes. The main challenges associated with nanostructured V2O5 cathodes are structural degradation, instability of the solid‐electrolyte interface layer, and poor electron conductance, which lead to low capacity and rapid decay of cyclic stability. Here, a novel composite structure of V2O5 nanoparticles encapsulated in 3D networked porous carbon matrix coated on carbon fibers (V2O5/3DC‐CFs) is reported that effectively addresses the mentioned problems. Remarkably, the V2O5/3DC‐CF electrode exhibits excellent overall lithium‐storage performance, including high Coulombic efficiency, excellent specific capacity, outstanding cycling stability and rate property. A reversible capacity of ≈183 mA h g−1 is obtained at a high current density of 10 C, and the battery retains 185 mA h g−1 after 5000 cycles, which shows the best cycling stability reported to date among all reported cathodes of lithium ion batteries as per the knowledge. The outstanding overall properties of the V2O5/3DC‐CF composite make it a promising cathode material of lithium ion batteries for the power‐intensive energy storage applications.

Artificial self-healing superhydrophobic surfaces have become a new research hotspot because of their recoverable non-wetting performance and practical perspective. In this paper, a superhydrophobic surface was fabricated by aerosol-assisted layer-by-layer chemical vapor deposition (AA-LbL-CVD) of epoxy resins and PDMS polymer films. The obtained samples still showed superhydrophobicity even after long-term exposure to different pH solutions and UV light irradiation as well as great mechanical stability against sandpaper abrasion and double-sided tape peeling. Importantly, due to the shape memory effect of the polymer films, the as-prepared samples could recover the previously crushed micro–nano structures upon heat treatment to make the surface superhydrophobic, showing thermo-triggered healing of superhydrophobicity.

Urchin-like ZnO@MnO2 core@shell nanostructures were synthesized via two step easy-controlled hydrothermal methods intercalated with a carbonization process. As a powder electrode, it showed improved electrochemical properties (∼59.4% retention of its initial capacitance even when current density increased 50 times and 111.3% of its original capacitance after 5000 long-term cycles) compared with bare MnO2 nanoflakes and many reported binder-free ZnO@MnO2 electrodes, which could be considered as high-rate and high-stability pseudocapacitor electrodes.