In situ hydrogels have attracted considerable attention in tissue engineering because of their minimal invasiveness and ability to match the irregular tissue defects. However, hydrous physiological environments and the high level of moisture in hydrogels severely hamper binding to the target tissue and easily cause wound infection, thereby limiting the effectiveness in wound care management. Thus, forming an intimate assembly of the hydrogel to the tissue and preventing wound infecting still remains a significant challenge. In this study, inspired by mussel adhesive protein, a biomimetic dopamine‐modified ε‐poly‐l‐lysine‐polyethylene glycol‐based hydrogel (PPD hydrogel) wound dressing is developed in situ using horseradish peroxidase cross‐linking. The biomimetic catechol–Lys residue distribution in PPD polymer provides a catechol–Lys cooperation effect, which endows the PPD hydrogels with superior wet tissue adhesion properties. It is demonstrated that the PPD hydrogel can facilely and intimately integrate with biological tissue and exhibits superior capacity of in vivo hemostatic and accelerated wound repair. In addition, the hydrogels exhibit outstanding anti‐infection property because of the inherent antibacterial ability of ε‐poly‐l‐lysine. These findings shed new light on the development of mussel‐inspired tissue‐anchored and antibacterial hydrogel materials serving as wound dressings.

Lead halide perovskites possess unique characteristics that are well-suited for optoelectronic and energy capture devices, however, concerns about their long-term stability remain. Limited stability is often linked to the methylammonium cation, and all-inorganic CsPbX 3 (X=Cl, Br, I) perovskite nanocrystals have been reported with improved stability. In this work, the photostability and thermal stability properties of CsPbX 3 (X=Cl, Br, I) nanocrystals were investigated by means of electron microscopy, X-ray diffraction, thermogravimetric analysis coupled with FTIR (TGA-FTIR), ensemble and single particle spectral characterization. CsPbBr 3 was found to be stable under 1-sun illumination for 16 h in ambient conditions, although single crystal luminescence analysis after illumination using a solar simulator indicates that the luminescence states are changing over time. CsPbBr 3 was also stable to heating to 250°C. Large CsPbI 3 crystals (34 � 5 nm) were shown to be the least stable composition under the same conditions as both XRD reflections and Raman bands diminish under irradiation; and with heating the γ (black) phase reverts to the nonluminescent δ phase. Smaller CsPbI 3 nanocrystals (14 � 2 nm) purified by a different washing strategy exhibited improved photostability with no evidence of crystal growth but were still thermally unstable. Both CsPbCl 3 and CsPbBr 3 show crystal growth under irradiation or heat, likely with a preferential orientation based on XRD patterns. TGA-FTIR revealed nanocrystal mass loss was only from liberation and subsequent degradation of surface ligands. Encapsulation or other protective strategies should be employed for long-term stability of these materials under conditions of high irradiance or temperature.[a] B.

In order to study the charge effect on the formation of an anion-templated silver cluster, a trivalent tetrahedral anion was incorporated into the silver assembly. A 26-nuclear silver cluster was prepared, and its structure was confirmed by single-crystal X-ray diffraction. Also, the resulting structure was characterized by powder X-ray diffraction data. Its light absorption and photoluminescent properties were studied by solid-state UV diffuse-reflectance and fluorescence spectroscopy. Compared with the other reported silver clusters with tetrahedral anion templates, the more negative VO 4 3− anion led to the formation of a bigger silver cluster. Also, the supramolecular motif O−H(CH 3 OH)•••O(trifluoroacetate) was confirmed on the cluster surface for the first time.

The integration of microfluidics and electrochemical cells is at the forefront of emerging sensors and energy systems; however, a fabrication scheme that can create both the microfluidics and electrochemical cells in a scalable fashion is still lacking. We present a one-step, mask-free process to create, pattern, and tune laser-induced graphene (LIG) with a ubiquitous CO2 laser. The laser parameters are adjusted to create LIG with different electrical conductivity, surface morphology, and surface wettability without the need for postchemical modification. Such definitive control over material properties enables the creation of LIG-based integrated open microfluidics and electrochemical sensors that are capable of dividing a single water sample along four multifurcating paths to three ion selective electrodes (ISEs) for potassium (K+), nitrate (NO3 –), and ammonium (NH4 +) monitoring and to an enzymatic pesticide sensor for organophosphate pesticide (parathion) monitoring. The ISEs displayed near-Nernstian sensitivities and low limits of detection (LODs) (10–5.01 M, 10–5.07 M, and 10–4.89 M for the K+, NO3 –, and NH4 + ISEs, respectively) while the pesticide sensor exhibited the lowest LOD (15.4 pM) for an electrochemical parathion sensor to date. LIG was also specifically patterned and tuned to create a high-performance electrochemical micro supercapacitor (MSC) capable of improving the power density by 2 orders of magnitude compared to a Li-based thin-film battery and the energy density by 3 orders of magnitude compared to a commercial electrolytic capacitor. Hence, this tunable fabrication approach to LIG is expected to enable a wide range of real-time, point-of-use health and environmental sensors as well as energy storage/harvesting modules.

A series of triphenylamine-based dyes (TPACR1, TPACR2, and TPACR3) with multiple corhodanine derivatives as acceptors were prepared and examined as sensitizers for dye-sensitized solar cells. The overall conversion efficiencies of DSSCs based on these dyes were in the range of 2.63 to 5.31%, in which TPACR2-based DSSC showed the best photovoltaic performance: a short-circuit current (J sc ) of 15.03 mA•cm −2 , an open-circuit voltage (V oc ) of 552 mV, and a fill factor (FF) of 0.64, corresponding to an overall efficiency of 5.31% under simulated AM 1.5 solar irradiation (100 mW• cm −2 ). Compared with monoanchoring TPACR1 dye and trianchoring TPACR3 dye, dianchoring TPACR2 dye had a relatively slower charge recombination rate between injected electrons and triphenylamine dye cations, which was indicated by transient absorption kinetics Furthermore, the suppression of the charge recombination between injected electron and the I 3 − in the electrolyte lead to the longer electron lifetime observed with the DSSC based on the TPACR2 dye. In comparison with the TPACR1 and TPACR3 dye, the TPACR2 dye showed the higher overall conversion efficiency with simultaneous enhancement of photocurrent and photovoltage.

Advancement of the synthesis and control of the self-assembly process of new high-nucleus silver clusters with desired structures is important for both the material sciences and the many applications. Herein, three new silver clusters, 20-, 22-, and 8-nucleus, based on alkynyl ligands were constructed and their structures were confirmed by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analyses, and Fourier-transform infrared spectroscopy (FT-IR). For the first time, the trivalent tetrahedron anion of AsO 4 3− , as a template, and the surface ligand of Ph 2 PO 2 H, with new coordination modes, were employed in preparation of the silver clusters. The role of surface ligands and template anions in the size and structure of the clusters was investigated. The presence of the template in the structure of the clusters led to the formation of the high-nucleus clusters. Also, in this report, it was shown that the participation of the template in the assembly of a cluster can be controlled by the surface ligands. UV−vis absorption and luminescent properties of the clusters and the thermal stability of the 8-nucleus cluster were also studied.

The first silver nanocluster with an octahedral template of TeO6 6– was synthesized as a neutral 36-nucleus nanocluster, and its structure was demonstrated using single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, electrospray ionization mass spectrometry, and X-ray photoelectron spectroscopy. The peripheral ligands of the cagelike skeleton of the nanocluster are CF3COO– and tBuCC–. During the synthesis, the TeO6 6– template arranged the nanocluster, and a 36-nucleus nanocluster was formed. The effect of the template nature was displayed on the structural features of the nanocluster in comparison with an 8-nucleus cluster, with the same synthesis conditions. The photoluminescence and UV–vis absorption analyses of the nanocluster were also investigated. The nanocluster displayed near-infrared luminescence emission at 690 nm.

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