Active packaging film was developed by incorporating Lycium barbarum fruit extract (LFE) into chitosan. The effects of LFE on physicochemical properties of the chitosan/LFE films were evaluated. When the weight ratio of LFE to chitosan was increased from 0:1 to 1:1, DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity of the chitosan/LFE films increased near ten-folds and reached up to 35.8%; water vapour permeability of the chitosan/LFE films decreased 43.0% from 5.67 g m mm À2 day À1 kPa À1 , and water solubility decreased from 100% to 24.52% because of interactions between LFE and hydrophilic groups of chitosan confirmed by FTIR. However, the chitosan/LFE films became darker after LFE was incorporated. The pure chitosan film showed better tensile strength (23.19 MPa) and elongation at break (22.29%) than the chitosan/LFE films (15.52 MPa and 9.58% for the one with weight ratio of LFE to chitosan of 0.6:1).

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Tin‐based perovskites are a promising candidates to replace their toxic lead‐based counterparts in optoelectronic applications, such as light‐emitting diodes (LEDs). However, the development of tin perovskite LEDs is slow due to the challenge of obtaining high‐quality tin perovskite films. Here, a vapor‐assisted spin‐coating method is developed to achieve high‐quality tin perovskites and high‐efficiency LEDs. It is revealed that solvent vapor can lead to in situ recrystallization of tin perovskites during the film‐formation process, thus significantly improving the crystalline quality with reduced defects. An antioxidant additive is further introduced to suppress the oxidation of Sn2+ and increase the photoluminescence quantum efficiency up to ≈30%, which is an approximately fourfold enhancement in comparison with that of the control method. As a result, efficient tin perovskite LEDs are achieved with a peak external quantum efficiency of 5.3%, which is among the highest efficiency of lead‐free perovskite LEDs.

Alkaline hydrogen peroxide (AHP) was investigated to enhance the content and functionality of soluble dietary fiber (SDF) extracted from black bean coats. Compared with the content of SDF of original black bean coat 7.8%, the content of SDF of modified black bean coat was 16.9% after treated by 15% H 2 O 2 (v/v) at pH 11 and 1:18 (w/v) as liquid-to-solid ratio for 0.5 h. Monosaccharide composition confirmed that the ratio of galacturonic acid in modified SDF (M-SDF) was higher than that of original SDF (O-SDF), and M-SDF was also with smaller molecular weight (Mw) of 1.24 ×10 6 Da and lower ζ-potential of −42.3 mV. Other structural characters were determined by FT-IR and TEM. In the range of 2-6% (w/v), both O-SDF and M-SDF showed a shear thinning behavior. The latter showed stronger gelation ability at the presence of Ca 2+ evaluated by dynamic oscillatory rheometry. Moreover, M-SDF exhibited good abilities of binding bile acids in vitro. It could be concluded that M-SDF had a great potential to be applied as a novel kind of functional ingredient or additive in food industry.

A novel sensing strategy for bisphenol A was designed based on graphene quantum dots and peroxidase.