Rechargeable aqueous zinc ion batteries (AZIBs) promise high energy density, low redox potential, low cost and safety; however, their cycle performances are seriously insufficient to restrict the progress in this field. We propose a new concept of atomic electrode formed on the graphdiyne (GDY). This new idea electrode was synthesized by selectively, uniformly, and stably anchoring Zn atoms on GDY at the beginning of plating. The Zn atoms are induced to grow into larger size Zn clusters, which continue to grow into nanoflat. Finally, a new heterojunction interface is formed on GDY without any Zn dendrites and side reactions, even at high current densities. Such stepwise induction of growth greatly suppresses the formation of Zn dendrites, resulting in high electroplating/stripping reversibility and lifespan of AZIBs.

Rational design and synthesis of non-precious metal-based electrocatalysts for efficient overall water splitting (OWS) in an integrated electrolyzer are of great significance for the development of hydrogen energy. To this end, nanowire-structured heterogenous MnCo 2 O 4 /graphdiyne arrays are synthesized on the surface of 3D carbon cloth (NW-MnCo 2 O 4 /GDY) by using in situ assembly and coupling strategy. Experiments demonstrated that the special core/shell-nanowire structure and synergistic interaction between the MnCo 2 O 4 and GDY can greatly improve the electric conductivity, facilitate the mass/ion transport and gas emissions, expose more active sites, and thus lead to the enhancement of the catalytic activity and long-term stability of the electrocatalysts for OWS. For example, the alkaline water electrolyzer assembled by NW-MnCo 2 O 4 /GDY shows high-performance with only 1.47 and 1.60 V required to reach a current density of 10 and 100 mA cm −2 , respectively, which is even better than that of previously reported electrocatalysts.

Giant vesicles (1-10 μm) were constructed via a facile ionic self-assembly (ISA) strategy using an anionic dye Acid Orange II (AO) and an oppositely charged ionic-liquid-type cationic surfactant 1-tetradecyl-3-methylimidazolium bromide (C14mimBr). This is the first report about preparing giant vesicles through ISA strategy. Interestingly, the giant vesicle could keep the original morphology during the evaporation of solvent and displayed solid-like properties at low concentration. Moreover, giant vesicles with large internal capacity volume and good stability in solution could also be achieved by increasing the concentrations of AO and C14mimBr which contributed to the increase of the other noncovalent cooperative interactions. In order to facilitate comparison, a series of parallel experiments with similar materials were carried out to investigate and verify the driving forces for the formation of these kinds of giant vesicles by changing the hydrophobic moieties or the head groups of the surfactants. It is concluded that the electrostatic interaction, hydrophobic effect and π-π stacking interaction play key roles in this self-assembly process. Importantly, the giant vesicles can act as a smart microcarrier to load and release carbon quantum dot (CQD) under control. Besides, the giant vesicles could also be applied as a microrector to synthesize monodispersed Ag nanoparticles with diameter of about 5-10 nm which exhibited the ability to catalyze reduction of 4-nitroaniline. Therefore, it is indicated that our AO/C14mimBr assemblies hold promising applications in the areas of microencapsulation, catalyst support, and lightweight composites owing to their huge sizes and large microcavities.

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Developing highly active, stable and low-cost electrocatalysts capable of efficient oxygen evolution reaction (OER) is urgent and challenging. Here we report a facile and general strategy for synthesizing the noble-metal-free...