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The instability of all-inorganic perovskites and poor understanding of the photoluminescence mechanisms have hindered their practical applications. While a large body of work on 3-D perovskite phases is available in the literature, the promising zero-dimensional (0-D) phase perovskite materials are still poorly understood. Herein, we report a new synthesis method for the production of 0-D Cs4PbBr6 perovskite quantum dots (QDs) in glass using a combination of Cs2CO3 concentration and heat-treatment temperature optimization. The differences in structure, morphology, and photoluminescence (PL) between the 0-D Cs4PbBr6 QDs and the 3-D CsPbBr3 QDs in glass were studied in detail. Cs4PbBr6 QD glass with high transmittance displayed a blue-shift PL emission centered at 503 nm, a narrow full width at half-maximum (fwhm, ∼20 nm), a high photoluminescence quantum yield (PLQY, ∼22%), and excellent long-term stability, thereby, advancing the study of these materials. It was demonstrated that Cs4PbBr6 displayed unique luminescent properties in correlation with the intrinsic defect states in the mid-band gap.

In this work, thin film composite polyamide (PA) membranes are modified by polyethyleneimine (PEI) and 2,6‐diaminopyridine (DAP) through sequential interfacial polymerization to fabricate contact active antibacterial membranes. The modified membranes show improved hydrophilicity and enhancement of zeta potential. Upon tethering with PEI and DAP onto the PA membranes, the membrane flux increases from 35.7 to 46.7 and 50.0 L m−2 h−1, respectively. Further the salt rejection rate improves from 96.6% to 98.0% and 98.8%, respectively. The PA‐PEI membranes have a better antibacterial performance than PA‐DAP, with a bacteria killing ratio for both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) over 96.7%, while a commercial LC LE‐4040 membrane presents bacteria killing ratio of 13.3% for E. coli and 8.4% for S. aureus, respectively.

In this work, nanocomposite membranes based on graphene and polylactide were evaluated for mechanical properties and biocompatibility. Single-layer graphene (SLG), graphene nanosheets (GNS), and poly L-lactic acid (PLLA) were prepared through layer-by-layer deposition and homogeneous mixing. The results revealed that PLLA/SLG nanocomposites and PLLA/GNS nanocomposites could show enhanced mechanical properties and biocompatibility. The addition of a tiny amount of SLG significantly improved Young’s modulus and tensile strength of the PLLA matrix by 15.9% and 32.8% respectively, while the addition of the same mass ratio of GNS boosted the elongation at break of the PLLA matrix by 79.7%. These results were ascribed to the crystallinity and interfacial interaction differences resulting from graphene incorporation. Also, improved biocompatibility was observed with graphene incorporation. Such nanocomposites membranes showed a lot of potential as environment-friendly and biomedical materials.

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