The lack of suitable cathodes is one of the key reasons that impede the development of aqueous zinc-ion batteries. Because of the inherently unsuitable structure and inferior physicochemical properties, the low-valent V2O3 as Zn2+ host could not be effectively discharged. Herein, we demonstrate that V2O3 (theoretical capacity up to 715 mAh g–1) can be utilized as a high-performance cathode material by an in situ anodic oxidation strategy. Through simultaneously regulating the concentration of the electrolyte and the morphology of the V2O3 sample, the ultraefficient anodic oxidation process of the V2O3 cathode was achieved within the first charging, and the mechanism was also schematically investigated. As expected, the V2O3 cathode with a hierarchical microcuboid structure achieved a nearly two-electron transfer process, enabling a high discharging capacity of 625 mAh g–1 at 0.1 A g–1 (corresponding to a high energy density of 406 Wh kg–1) and cycling stability (100% capacity retention after 10 000 cycles). This work not only sheds light on the phase transition process of low-valent V2O3 but also exploits a method toward design of advanced cathode materials.

A photocatalytic strategy has been developed to synthesize colloidal Ag-TiO2 nanorod composites in which each TiO2 nanorod contains a single Ag nanoparticle on its surface. In this rational synthesis, photoexcitation of TiO2 nanorods under UV illumination produces electrons that reduce Ag(I) precursor and deposit multiple small Ag nanoparticles on the surface of TiO2 nanorods. Prolonged UV irradiation induces an interesting ripening process, which dissolves the smaller nanoparticles by photogenerated oxidative species and then redeposits Ag onto one larger and more stable particle attached to each TiO2 nanorod through the reduction of photoexcited electrons. The size of the Ag nanoparticles can be precisely controlled by varying the irradiation time and the amount of alcohol additive. The Ag-TiO2 nanorod composites were used as electron transport layers in the fabrication of organic solar cells and showed notable enhancement in power conversion efficiency (6.92%) than pure TiO2 nanorods (5.81%), as well as higher external quantum efficiency due to improved charge separation and transfer by the presence of Ag nanoparticles.

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One-dimensional (1D) carbon nanomaterials wrapped by silver nanoparticles were fabricated via a facile and environmentally benign route with the assistance of supercritical carbon dioxide. Transmission electron microscopy, scanning electron microscopy, and energy-dispersive X-ray analysis revealed that carbon nanofibers (CNFs) were densely coated by silver nanoparticles under the optimized experimental condition. In the case of carbon nanotube/silver (CNT/Ag) nanohybrids, these silver nanoparticles on the surface of carbon nanotubes were predominantly spherical in shape with excellent dispersion, and their sizes were smaller than that on carbon nanofibers. The UV−vis spectra presented a surface plasmon resonance vibration band at 448 and 414 nm for CNFs and CNTs, respectively. X-ray diffraction analysis showed that the nanoparticles were of a face centered cubic structure. Some crucial factors, which affect the growing and arraying of Ag nanoparticles along the axis of 1D carbon nanomaterials, had been investigated. As examples for promising applications, the antibacterial activities of the as-prepared one-dimensional nanocomposites were also studied.

The transpassive dissolution of Ni in acidic sulfate media, including the influence of crystallographic orientation, was investigated. The surface plane had low index values, that is (100), (110), and (111). This study was largely based on the analysis of complex impedance. (100) and (110) specimens showed identical electrochemical behaviors, whereas the (111) specimen showed a current density about 20% lower. A reaction mechanism describing the dissolution of the passive film was proposed. This dissolution step was postulated to be catalytic, in the sense that the passive film transformed into a soluble species by anion was not consumed by the transpassive dissolution itself. Calculated polarization curves as well as electrode impedances at various polarization points were in a good agreement with experimental results.

Structural modulation endows electrochemical hybrids with promising energy storage properties owing to their adjustable interfacial and/or electronic characteristics. For MXene‐based materials, however, the facile but effective strategies for tuning their structural properties at nanoscale are still lacking. Herein, 3D crumpled S‐functionalized Ti3C2Tx substrate is rationally integrated with Fe3O4/FeS heterostructures via coprecipitation and subsequent partial sulfurization to induce a highly active and stable electrode architecture. The unique heterostructures with tuned electronic properties can induce improved kinetics and structural stability. The surface engineering by S terminations on the MXene further unlocks extra (pseudo)capacitive lithium storage. Serving as anode for lithium storage, the optimized electrode delivers an excellent long‐term cycling stability (913.9 mAh g−1 after 1000 cycles at 1 A g−1) and superior rate capability (490.4 mAh g−1 at 10 A g−1). Moreover, the (de)lithiation pathways associated with energy storage mechanisms are further revealed by operando X‐ray diffraction, in situ electroanalytical techniques, and first‐principles calculations. The hybrid electrode is proved to undergo stepwise phase transformations during discharging but a relatively uniform reconversion during charging, suggesting an asymmetric conversion mechanism. This work provides a novel strategy for designing high‐performance hybrids and paves the way for in‐depth understanding of complex lithium intercalation and conversion reactions.

As a typical double-crystalline diblock copolymer, polyethylene-b-poly(ethylene oxide) (PE-b-PEO) has been successfully modified on single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) using a simple supercritical carbon dioxide (SC CO2) antisolvent-induced polymer epitaxy method. The characterization results of transmission electron microscopy (TEM) demonstrated that the unique double-crystalline block copolymer PE-b-PEO can be periodically decorated along carbon nanotubes (CNTs), leading to a novel amphiphilic nanohybird structure. The effect of different solvents on the decorated patterns of PE-b-PEO on CNTs has been discussed in this work. We found that the selectivity of solvent to the segments of block copolymer played a decisive role on the morphology of PE-b-PEO assembling on CNTs. When 1,2-dichlorobenzene (DCB) or p-xylene was used as the solvent, PE-b-PEO formed periodic patterns on CNTs, where the nanotube-induced PE crystallization was critical to the formation of the novel regular nanohybird structure. When the solvent was switched to N,N -dimethylacetamide (DMAc), which was more selective for PEO, periodic patterns were not observed, and merely the thin polymer coatings were observed on CNTs. The experimental results indicated that the decorating degree of PE-b-PEO on the surface of CNTs increased significantly with the increase of SC CO2 pressure. FT-IR and Raman spectra indicated that there existed multiple weak molecular interactions between polymer chains and CNTs. Therefore, we anticipate this work may lead to a controllable method making use of peculiar properties of SC CO2 to help to fabricate the functional CNTs-based nanocomposties containing diblock copolymer with the various micromorphologies in the different organic solvents.