The surface of a polysulfone membrane was modified with a bioinspired polydopamine (PDA) film followed by the in situ formation of silver nanoparticles (AgNPs) to mitigate membrane biofouling. The PDA modification enhanced the membrane's bacterial anti-adhesive properties by increasing the surface hydrophilicity, while AgNPs imparted strong antimicrobial properties to the membrane. The AgNPs could be generated on the membrane surface by simply exposing the membrane to AgNO 3 solutions. Ag + ions were reduced by the catechol groups in PDA; the AgNP mass loading increased with exposure time, and the AgNPs were firmly immobilized on the membrane through metal coordination. During leaching tests, the concentrations of Ag + ions released were 2−3 orders of magnitude lower than the established contaminant limit for drinking water, thereby providing a safe antimicrobial technology. This novel membrane surface modification technique paves a way to mitigating biofouling by enhancing the membrane's anti-adhesive and antimicrobial properties, simultaneously.

Building framework materials with desirable properties and enhanced functionalities with nanocluster/superatom complexes as building blocks remains a challenge in the field of nanomaterials. In this study, the chiral [Au1Ag22(S‐Adm)12]3+ nanocluster/superatom complex (SC, in which S‐Adm=1‐adamantanethiol) was employed as a building block to construct the three‐dimensional (3D) superatom complex inorganic framework (SCIF) materials SCIF‐1 and SCIF‐2 through inorganic SbF6− linkers. SCIF‐1 is racemic due to the assembly of two SC enantiomers in a single crystal. In SCIF‐2, the SC enantiomers are packed in separate crystals, thus producing larger channels and a circularly polarized luminescence (CPL) response. These two 3D SCIF materials exhibit unique sensitive photoluminescence (PL) in protic solvents. Our study provides a new pathway for creating novel open‐framework materials with superatom complexes and a foundation for the further development of 3D framework materials for sensing and other applications.

Membrane systems are used increasingly for water treatment, recycling water from wastewater, during food processing, and energy production. They thus are a key technology to ensure water, energy, and food sustainability. However, biofouling, the build-up of microbes and their polymeric matrix, clogs these systems and reduces their efficiency. Realizing that a microbial film is inevitable, we engineered a beneficial biofilm that prevents membrane biofouling, limiting its own thickness by sensing the number of its cells that are present via a quorum-sensing circuit. The beneficial biofilm also prevents biofilm formation by deleterious bacteria by secreting nitric oxide, a general biofilm dispersal agent, as demonstrated by both short-term dead-end filtration and long-term cross-flow filtration tests. In addition, the beneficial biofilm was engineered to produce an epoxide hydrolase so that it efficiently removes the environmental pollutant epichlorohydrin. Thus, we have created a living biofouling-resistant membrane system that simultaneously reduces biofouling and provides a platform for biodegradation of persistent organic pollutants.

Amide bond formation is one of the most important basic reactions in chemistry. A catalyst‐free approach for constructing amide bonds from thiocarboxylic acids and amines was developed. The mechanistic studies showed that the disulfide was the key intermediate for this amide synthesis. Thiobenzoic acids could be automatically oxidized to disulfides in air, thioaliphatic acids could be electro‐oxidized to disulfides, and the resulting disulfides reacted with amines to give the corresponding amides. By this method, various amides could be easily synthesized in excellent yields without using any catalyst or activator. The successful synthesis of bioactive compounds also highlights the synthetic utility of this strategy in medicinal chemistry.

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