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Silver nanowires (AgNWs) have been considered as a promising candidate for transparent stretchable conductors (TSCs). However, the strong interface mismatch of stiff AgNWs and elastic substrates leads to the stress concentration at their interface and ultimately the low stretchability and poor durability of TSCs. Here, to address the interfacial mismatch of AgNWsbased TSCs we put forward a universal interface tailoring strategy that introduces the mercapto compound as the intermediate crosslinked layer. The mercapto compound strongly interacts with the AgNWs, forming a dense protective layer on their surface to improve their corrosion resistance, and reacts with the polymer substrate, forming a buffer layer to release the concentrated stress. As a result, the optimized TSCs showed superior stretchability (160%), exceptional durability (230 000 cycles), competent optoelectrical performance (18.0 ohm•sq −1 with a transmittance of 86.5%), and prominent stability. This work provides clear guidance and a strong impetus for the development of transparent stretchable electronics.

In this contribution, we thoroughly investigated the ring-opening alternating copolymerization (ROAC) of cyclic anhydride and epoxide by using commercially available alkali metal carboxylates (AMCs) as the simple and green initiators. The idea of our work is based on the coordination effects of epoxide on an AMC and the formation of AMC–epoxide adducts, which will weaken the interaction between metal cation and its carboxylate counterion and therefore render the carboxylate to feasibly attack epoxides in a nucleophilic manner at high temperature. The coordination effects of epoxide on the AMC could be proved by Fourier transform infrared (FT-IR) spectroscopy and density functional theory (DFT) calculations. AMCs could effectively catalyze the copolymerization of phthalate anhydride (PA) and cyclohexene oxide (CHO) in bulk at 110 °C, affording polyesters with perfectly alternating structure. Potassium acetate (KOAc) was able to copolymerize some common cyclic anhydrides and epoxide, allowing for the preparation of polyesters with structural diversity. Of note, KOAc could mediate ROAC of PA with propylene oxide (PO) with a high molar feed ratio of [KOAc]/[PA]/[PO] = 1:20 000:150 000, affording poly­(PA-alt-PO) with high molecular weight (>100 kDa). Finally, two different polymerization mechanisms, including anionic polymerization and cooperative catalysis, have been proposed according to the interaction strength between metal cation and carboxylate anion. In the “cooperative catalysis” mechanism, the alkali metal cation served as the Lewis acid to activate epoxide and cyclic active species were generated.

Block polymers offer unparalleled opportunities for designing materials with enhanced functionalities and properties. Hence, we report a synthetic strategy for diblock polyesters through bridging two distinct reactions between ring-opening polymerization of lactide (LA) and ring-opening copolymerization of epoxides with anhydrides by using a binary catalyst. Specifically, in the terpolymerization of LA, epichlorohydrin (ECH), and phthalic anhydride (PA), spectroscopy indicated that this process occurs first by ECH/PA copolymerization and then homopolymerization of LA, forming diblock polyester. Density functional theory (DFT) calculations revealed that coupling of ECH/PA was more favorable than LA homopolymerization in the presence of PA, while an incorporation of LA into the ECH−PA sequence was also possible owing to the competitive energy barriers and thermodynamic priority. It was also computationally found that LA homopolymerization occurred after consumption of PA to achieve diblock polyester, as experimentally observed. Furthermore, the diblock polyester architectures could be extended and modified by introducing various monomers.

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WO3/ZrO2 catalysts prepared by different methods are distinct in their catalytic behaviour. In this work, WO3/ZrO2 catalysts prepared by impregnating Zr(OH)4 and crystallized ZrO2 and then calcining at selected temperatures were characterized by means of qualitative and quantitative Raman spectroscopy. The results showed that ZrO2 in WO3/ZrO2 obtained from crystallized ZrO2 (referred to as WZ) is monoclinic, whereas ZrO2 in WO3/ZrO2 obtained from Zr(OH)4 (referred to as WZH) is in a metastable tetragonal phase as long as the WO3 content is high enough. In both WZ and WZH, WO3 is dispersed on ZrO2 as a monolayer, and the dispersion capacity per 100 m2 of ZrO2 is in good agreement with that estimated from the close‐packed monolayer model. However, since the specific surface areas of WZH samples are larger than those of WZ samples, the dispersion capacity per gram of ZrO2 of WZH is larger than that of WZ. A chemical reaction may occur between WO3 and the surface of Zr(OH)4 (or tetragonal ZrO2) at high temperature, and then some superacid sites are created on the surface of the WZH sample.

To accurately monitor the variations of lysosomal nitric oxide (NO) under physiological condition remains a great challenge for understanding the biological function of NO. Herein, we developed a new chemotype probe, namely, MBTD, for acid-promoted and far-red fluorescence imaging of lysosomal NO in vitro and ex vivo. MBTD was rationally designed by incorporating o-phenylenediamino (OPD) moiety into the donor-acceptor-donor (D-A-D) type fluorophore based on a dual intramolecular charge transfer (ICT) mechanism. Compared to previously reported OPD-based NO probes, MBTD displays several distinct advantages including large stroke shift, huge on-off ratio with minimal autofluorescence, and high NO specificity. Particularly, MBTD exhibits an acid-promoted response to NO with high acid tolerance, which greatly improves the spatial resolution to lysosomal NO by excluding the background noise from other nonacidic organelles. Furthermore, MBTD displayed much longer-lived and more stable fluorescence emission in comparison with the commercialized NO probe. MBTD was employed for ratiometric examination of the exogenous or endogenous NO of macrophages. More importantly, MBTD was able to detect the variation of lysosomal NO level in an acute liver injury mouse model ex vivo, implying the potential of MBTD for real-time monitoring the therapeutic efficacy of drug candidates for the treatment of acute liver injury. MBTD as a novel type of NO probe might open a new avenue for precisely sensing lysosomal NO-related pathological and therapeutic process.