The development of high‐efficiency electrocatalysts for large‐scale water splitting is critical but also challenging. In this study, a hierarchical CoMoSx chalcogel was synthesized on a nickel foam (NF) through an in situ metathesis reaction and demonstrated excellent activity and stability in the electrocatalytic hydrogen evolution reaction and oxygen evolution reaction in alkaline media. The high catalytic activity could be ascribed to the abundant active sites/defects in the amorphous framework and promotion of activity through cobalt doping. Furthermore, the superhydrophilicity and superaerophobicity of micro‐/nanostructured CoMoSx/NF promoted mass transfer by facilitating access of electrolytes and ensuring fast release of gas bubbles. By employing CoMoSx/NF as bifunctional electrocatalysts, the overall water splitting device delivered a current density of 500 mA cm−2 at a low voltage of 1.89 V and maintained its activity without decay for 100 h.

It is known that the polyamide (PA) barrier layer’s inherent microstructure and surface physicochemical properties of thin film composite nanofiltration membrane are crucial for its separation performance. Herein, we designed and synthesized a new zwitterionic aromatic diamine monomer 3-(4-(2-((4-aminophenyl)­amino)­ethyl)­morpholino-4-ium)­propane-1-sulfonate (PPD-MEPS) through a three steps reaction, and this hydrophilic molecule was incorporated into the active layer to tailor the poly­(piperazine-amide)-based nanofiltration membranes with significantly improved water permeability and antifouling properties. As a p-phenylenediamine (PPD) derivative, PPD-MEPS possesses two active amine units, which can react with trimesoyl chloride in the organic phase during the interfacial polymerization reaction process. Thus, the super-hydrophilic zwitterions were not only on the membrane surface but also across the whole PA layer to facilitate water molecule transportation. The successful augmentation of zwitterions into the PA layer was well illustrated by attenuated total reflectance–Fourier transform infrared spectroscopy (ATR–FTIR) results and X-ray photoelectron spectroscopy analysis. With increasing loading content of PPD-MEPS in PIP aqueous solution, the as-fabricated nanofiltration membranes (NFMs) exhibited higher hydrophilicity, increased active layer thickness, and molecular weight cut off. When the zwitterionic monomer reached 60% to PIP for NFM-4, the water permeability went up to 9.82 L m–2 h–1 bar–1, increasing by 45%; meanwhile, the Na2SO4/NaCl selectivity increased from 2.54 to 4.03. In addition, the fouling experiments illustrated that the fouling resistance of the zwitterion-modified NFMs to bovine serum albumin was significantly improved.

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Hollow dendritic Ag/Pt alloy nanoparticles were synthesized by a double template method: Ag nanoparticles as the hard template to obtain hollow spheres by a galvanic replacement reaction between PtCl and metallic Ag and surfactant micelles (Brij58) as the soft template to generate porous dendrites. The formation of a Ag/Pt alloy phase was confirmed by XRD and HRTEM. Elemental mapping and line scanning revealed the formation of the hollow architecture. We studied the effects of the Ag/Pt ratio, surfactant and reaction temperature on the morphology. In addition, we explored the formation process of hollow dendritic Ag/Pt nanoparticles by tracking the morphologies of the nanostructures formed at different stages. In order to improve the electrocatalytic property, we controlled the size of the nanoparticles and the thickness of the shell by adjusting the amount of the precursor. We found that these Ag/Pt alloy nanoparticles exhibited high activity (440 mA mg) and stability as an electrocatalyst for catalyzing methanol oxidation.

Developing techniques of advanced patterning for colloidal nanocrystals (NCs) is essential to construct high-performance electronic/optoelectronic devices. However, conventional NC patterning methods require complicated photolithography processes and/or delicately designed photocrosslinkers. Here, we develop a direct, photoresist-free method to pattern functional NCs while avoiding any photosensitive molecules. In our approach, the solubility of NCs is switched through cleaving native organic ligands under UV light exposure. Developing with the mother solvent produces fine patterns with feature sizes (as low as 10 μm) comparable to that of conventional photolithography. Importantly, the obtained patterns of NCs allow postpatterning ligand exchange. As representatives, we demonstrate patterned NC-based thin-film transistors (TFTs) and quantum dot light-emitting diodes (QLEDs). The In2O3 NC-based TFTs are turned from inactive to active using the patterning process and display substantially enhanced electronic performances upon ligand exchange with inorganic ligands. Furthermore, exquisite fluorescence quantum dot (QD) patterns are enabled. The QLEDs fabricated with ZnCl2-treated green QD patterns exhibit electroluminescence performances that are comparable to those of unpatterned QLEDs. Our strategy offers a powerful yet simple patterning technique for fabricating low-temperature thin-film electronics and optoelectronics, which is expected to be a versatile and extensible approach for solution-processed NC-based thin-film device manufacturing.