Surface topological glycosylation enhances mucoadhesion of bacteria.

Comprehensive Summary

Sugar moieties present on bacterial surface serve as pivotal regulators of bacterial activity. Precisely adjusting the abundance and distribution of surface sugar moieties can offer an important approach to manipulating bacterial behavior, but has been proven to be difficult. Herein, surface topological glycosylation is reported to mediate the interaction of bacteria with mucous layer. Alkynes functionalized by sugar moieties with different branching are synthesized through iterative Michael addition and amide condensation reactions. By a copper-catalyzed azide-alkyne cycloaddition, the resulting compounds with different branching structures can be attached onto bacterial surface that is modified with azido groups. As a proof-of-concept study, a set of topologically glycosylated probiotics (TGPs) is prepared using linear, two-branched, and tetra-branched compounds, respectively. The interaction between mucin and TGPs was studied and the results demonstrate that, compared to unmodified bacteria, TGPs exhibit an enhanced adhesive capacity to mucin, which increases with the branching numbers. Similar binding trend is observed in ex vivo colonic mucus adhesion experiments and bacteria glycosylated with tetra-branched compounds display the highest binding efficiency. This work proposes a chemical method to tune the abundance and distribution of sugar moieties on bacteria, providing unique significant insights into the manipulation of bacterial behavior through surface modification.

The free-standing multiscale porous NiFeCoZn high-entropy-alloy is in-situ constructed on the surface of NiZn intermetallic and Ni heterojunction over nickel foam (NiFeCoZn/NiZn-Ni/NF) by one scalable electroplating-annealing-etching protocal. The as-made NiFeCoZn/NiZn-Ni/NF fulfills the outstanding electrocatalytic performances with the small overpotentials (η ₅₀₀ = 184/348 mV), low Tafel slopes, as well as exceptional long-term catalytic durability for 400 h in alkaline solution toward both hydrogen evolution reaction and oxygen evolution reaction.

Comprehensive Summary

In the endeavor of searching for highly active and stable electrocatalysts toward overall water splitting, high-entropy-alloys have been the intense subjects owing to their advanced physicochemical property. The non-noble metal free-standing multiscale porous NiFeCoZn high-entropy-alloy is in situ constructed on the surface layer of NiZn intermetallic and Ni heterojunction over nickel foam (NiFeCoZn/NiZn-Ni/NF) by one scalable dealloying protocal to fulfill the outstanding bifunctional electrocatalytic performances toward overall water splitting. Because of the high-entropy effects and specific hierarchical porous architecture, the as-made NiFeCoZn/NiZn-Ni/ NF displays high intrinsic catalytic activities and durability toward both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media. In particular, the in-situ construction of bimodal porous NiFeCoZn high-entropy-alloy results in the small overpotentials (η ₁₀₀₀ = 254/409 mV for HER and OER), low Tafel slopes, and exceptional long-term catalytic durability for 400 h. Expressively, the electrolyzer constructed with NiFeCoZn/NiZn-Ni/NF as both cathode and anode exhibits a low cell voltage of 1.72 V to deliver the current density of 500 mA·cm^–2 for overall water splitting. This work not only provides a facile and scalable protocol for the preparation of self-supporting high-entropy-alloy nanocatalysts but also enlightens the engineering of high performance bifunctional electrocatalysts toward water splitting.

Carbon dots (CDs)-based long persistent luminescence (LPL) composites with a tunable duration in an ultrawide range from second- to hour-level are designed and prepared for the first time. The relationship of energy levels between excited states of CDs and charged-transfer (CT) states of the corresponding composites plays a pivotal role in activating LPL and regulating the LPL durations. These LPL composites have been preliminarily employed in dynamic displaying systems.

Comprehensive Summary

Duration-tunable afterglow materials have garnered considerable attention in various applications. Herein, carbon dots (CDs)-based long persistent luminescence (LPL) composites with a tunable duration in an ultrawide range of seconds-to-hours levels were designed and prepared for the first time. In contrast to the established CD-based afterglow materials, we reported that CD-based composites exhibit LPL in the form of exciplexes and long-lived charge-separated states, enabling the LPL to be prolonged from several seconds to over one hour, exceeding the typical regulation range (limited to 1 min). Further studies revealed that the relationship between the excited and charge-transfer states of CDs plays a pivotal role in activating the LPL and regulating its duration. Furthermore, these composites exhibited high photoluminescence (PL) quantum yields of up to 60.63%, and their LPL was robust under ambient conditions, even in aqueous media. Their robust and superior LPL performance endows these composites with a strong competitive advantage in dynamic display systems, such as tags for time-resolved data encryption and displays of the remaining time of takeaways. This study offers an approach to preparing CDs-based LPL composites with tunable durations and may provide new insights for the development of rare-earth-free LPL materials.

Comprehensive Summary

In the last few years, organic solar cells (OSCs) have made significant progress in photovoltaic performance, mainly due to the innovative development of active layer materials, especially Y-series and related derivatives as acceptors which have become the key factor that boosts the power conversion efficiency. Recently, to achieve high-performance OSCs, an emerging molecular design strategy of applying flexible alkyl units as linkers to construct non-fully conjugated acceptors has been developed and addressed great attention. This review highlights the non-fully conjugated photovoltaic materials with Y-series backbone that enable high-performance OSCs. Impressive OSCs have been achieved by some representative non-fully conjugated material systems. The related molecular design strategies are discussed in detail. Finally, a brief summary and future prospect are provided in advancing the non-fully conjugated photovoltaic materials with Y-series backbone towards the brighter future.

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