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Pharmaceuticals and personal care products (PPCPs), an emerging class of highly recalcitrant water contaminants, have raised considerable concerns in environment community. Graphitic carbon nitride (CN) has shown a great potential towards the photodegradation of water contaminants under visible light irradiation. However, the conventional bulk CN (BCN) presents the amorphous structure, resulting in an inefficient yield of hydroxyl radicals (•OH) for the complete mineralization of PPCPs. This study provides fundamental insights into significantly enhancing the hydroxyl radical generation via improving the crystallinity of the pristine CN materials. Experimental measurements and accompanying density functional theory (DFT) computational analysis suggest that the crystalline carbon nitride (CCN) exhibited an enhanced adsorption ability towards the dissolved O 2. Upon the light irradiation, the adsorbed O 2 molecules readily undergo a direct two-electron reduction reaction on the CCN surface, instead of the conventional two successive single-electron reduction reactions on the BCN surface, to produce H 2 O 2 subsequently converting into •OH radicals. Along with the improved charge separation efficiency and electron transfer ability, CCN-based materials show superior photocatalytic activity towards PPCPs-type pollutants, compared with the pristine BCN catalysts. Importantly, the catalyst show excellent photodegradation activities under natural sunlight irradiation, at low PPCPs concentration (20 μg/L), in the mixed PPCPs solution or in the real wastewater/water samples, indicating the potential of CCN to enable practical ex situ destructive treatment of PPCPs-contaminated groundwater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

It is of technical and economic importance to develop an effective cosmetic ingredient against skin aging through low-cost and facile production. This study developed a polymer/layered silicate nanocomposite as cosmetic ingredient against skin aging. Firstly, quaternized carboxymethyl chitosan (QCMC)/organic montmorillonite (OMMT) nanocomposite (QCOM) was fabricated via solution-induced intercalation. QCOM with different mass ratios of QCMC to OMMT were studied by various characterizations as well as moisture-adsorption and retention activities and UV-protection capacity. QCOM was then added into a cosmetic formulation to prepare a cosmetic cream. And the evaluation of its efficacy about skin care was conducted. The results showed that the optimal QCOM had better moisture-adsorption and retention behaviors than hyaluronic acid, and QCOM solution displayed good UV-protection ability. Furthermore, the QCOM-containing cosmetic cream meets the hygienic standard for cosmetics; it has negligible dermal irritation and a prominent moisture-retention efficacy on human stratum corneum., (Copyright © 2017 Elsevier Ltd. All rights reserved.)