Hexagonal boron nitride nanosheets (BNNSs) possess ultimate thermal and chemical stabilities and mechanical strengths. However, the unmodified BNNSs are hydrophobic and insoluble in water, which hinders their use in many technological areas requiring aqueous compatibility. In this work, h-BN was treated with molten citric acid to produce aqueous dispersible boron nitride sheets (ca-BNNSs). The resultant ca-BNNSs were used to fabricate ca-BNNS/polyacrylamide (i.e., BNNS2.5/PAAm) nanocomposite hydrogels, targeting high water retentivity and flexibility. The BNNS2.5/PAAm hydrogel (initially swollen in water) largely remained swollen (water content ∼94 wt%) even after one-year storage under ambient conditions. Importantly, the swollen BNNS2.5/PAAm hydrogel (water content ∼95 wt%) was highly flexible. Its elongation and compressive strength exceeded 10,000% and 8 MPa at 97% strain, respectively. Moreover, the aforementioned hydrogel recovered upon the removal of compression force, without obvious damage. The substantially improved water retentivity and flexibility revealed that BNNSs can serve as a promising new platform in the development of high-performance hydrogels.

Converting the NO from gaseous pollutant into NH through electrocatalytical reduction using cost-effective materials holds great promise for pollutant purifying and resources recycling. In this work, we developed a highly selective and stable catalyst CoSe nanoparticle hybridized with carbon nanotubes (CoSe@CNTs). The CoSe@CNTs hybrid catalysts performed an extraordinary high selectivity for NH formation in NO electroreduction with minimal NO production and H evolution. The specific spatial structure of CoSe is conductive to the predominant formation of N-H bond between the N from adsorbed NO and H and inhibition of N-N formation from adjacent adsorbed NO. It was also the first time to convert the coordinated NO into NH using non-noble metal catalysis. Moreover, the original concept of employing CoSe as eletrocatalyst for NO hydrogenation presented in this work can broaden horizons and provide new dimensions in the design of new highly efficient catalysts for NH synthesis in aqueous solution.

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Several perylenediimide‐based chromophores with peripheral benzanthrone groups were developed and characterized for their third‐order nonlinear optics properties by using the femtosecond Z‐scan technique. As a consequence, these chromophores were found to exhibit a moderate two‐photon absorption cross‐section value, and the largest one was found to be 1072.81 GM.