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Interfacial solar seawater desalination is considered as one of the most promising sustainable techniques for producing fresh water. Janus hydrogel evaporators with a hydrophobic top layer and a hydrophilic bottom layer have been demonstrated as an effective way to accelerate water evaporation and reject salt ions. However, the existing strategies make it difficult to achieve precise control over surface wettability and confine a thin hydrophobic layer to the hydrogel's surface, both of which were considered to have a significant impact on solar seawater desalination. Herein, we fabricated amphiphilic Janus patch-grafted hydrogel evaporators, in which ultrathin hydrophobic polystyrene patches were uniformly and discretely distributed on the top of the hydrogel and hydrophilic quaternized poly(4-vinyl pyridine)s (QP4VPs) were entangled within the hydrogel network. By the rational design of the Janus patch size and surface coverage, the wettability of Janus hydrogels could be precisely regulated. The Janus hydrogel resulted in optimized solar water evaporation performance with an evaporation rate of 3.2 kg m−2 h−1 and Janus patch surface coverage of ∼60%. Moreover, the Janus hydrogel has a superior salt ion rejection ratio, which was attributed to the high ionic strength of the QP4VP-rich entangled layer. The amphiphilic Janus patch-grafted hydrogels outperformed all non-photothermal hydrogels and were comparable to photothermal hydrogels, in terms of water evaporation rate and salt ion rejection ratio, demonstrating their potential for solar seawater desalination. [ABSTRACT FROM AUTHOR]

Herein, efficient fabrication of polymersomes that have unique and nonequilibrium morphologies is reported. Starting from preparing big polymeric vesicles sized around 2 µm with a flexible but crosslinkable structure, a controllable morphological transformation process from the vesicles via prolate vesicles and the pearl‐chain‐like structure, which are the two intermediate structures, to vesicle‐end‐capped tubes is conducted. Significantly, each of the intermediates is a regular polymersome and occupies a distinct phase space in the transformation process and thus can be separately processed and prepared. By crosslinking the structures, respectively, regular polymersomes with unique but stable morphologies are fabricated. Furthermore, the 1D polymersomes contain narrow necks. These narrow necks are sensitive to ultrasound vibration and broken by gentle ultrasound treatment to form regular open‐ended tubes and open‐ended vesicles, which are nonequilibrium but stable morphologies and difficult to prepare by existing methods. [ABSTRACT FROM AUTHOR]

In this work, hybrid carbon/ZnxCo3−xO4 (ZCO) nanotube (HCNT) networks have been efficiently prepared, using highly pure, uniform and long core-crosslinked polymeric worm-like micelles (PWs) with a small diameter and a 3D interacting shell as the 1D template. The HCNTs have a diameter of 50 nm, a channel of 30 nm width, and a hybrid porous wall in which large amounts of open micropores (ca. 5 nm) and ZCO nanoparticles (NPs, <5 nm) are uniformly distributed. The network is formed by closely stacked HCNTs and has a high specific interfacial area (up to 825 m2 g−1) and open hierarchical pores. When used for lithium storage, the anode prepared from the network has excellent electrochemical performance including high capacity (up to 1124 mA h g−1 at 1 A g−1), good rate performance and excellent cycling stability (90% capacity remains after 600 cycles at 1 A g−1). For the preparation of the networks, the abovementioned PWs with PEG as the shell and a width of 28 nm can be efficiently prepared. During hybridization, the strong 3D interaction between the PEG chains and Zn2+/Co2+ inhibited the zeolitic imidazolate frameworks (ZIFs) to form individual crystalline particles of intrinsic size and shape. Instead, the ZIF crystals deformed and fused together to form a uniform hybrid layer, ca. 30 nm thickness, in which the PEG chains penetrated into the crystalline structure of ZIFs. In the layer, Zn and Co were homogeneously mixed and the Co/Zn ratio was conveniently adjusted. When the Co/Zn ratio was 2, the hierarchically porous network of carbon/ZnCo2O4 nanotubes with excellent electrochemical performance was finally obtained. [ABSTRACT FROM AUTHOR]