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Surgical site infections (SSIs) related to implants have always been a major challenge for clinical doctors and patients. Clinically, doctors may directly apply antibiotics into the wound to prevent SSIs. However, this strategy is strongly associated with experience of doctors on the amount and the location of antibiotics. Herein, an in situ constructable sol-gel system is developed containing antibiotics during surgical process and validated the efficacy against SSIs in beagles. The system involves chitosan (CS), β-glycerophosphate (β-GP) and vancomycin (VAN), which can be adsorbed onto porous hydroxyapatite (HA) and form VAN-CS/β-GP@HA hydrogel in a short time. The VAN concentration from VAN-CS/β-GP@HA hydrogel is higher than minimum inhibitory concentration (MIC) against Staphylococcus aureus (S. aureus) at the 21st day in vitro. In an in vivo canine model for the prevention of SSIs in the femoral condyle, VAN-CS/β-GP@HA exhibits excellent biocompatibility, antimicrobial properties, and promotion of bone healing. In all, the CS/β-GP instant sol-gel system is able to in situ encapsulate antibiotics and adhere on artificial bone implants during the surgery, effectively preventing SSIs related to implants., (© 2024 Wiley‐VCH GmbH.)

Zinc-ion batteries, in which zinc ions and protons do intercalation and de-intercalation during battery cycling with various proposed mechanisms under debate, have been studied. Recently, electrolytic zinc-manganese batteries, exhibiting the pure dissolution-deposition behavior with a large charge capacity, have been accomplished through using electrolytes with Lewis acid. However, the complicated chemical environment and mixed products hinder the investigation though it is crucial to understand the detailed mechanism. Here, cyclic voltammetry coupled electrochemical quartz crystal microbalance (EQCM) and ultraviolet-visible spectrophotometry (UV-Vis) are respectively, for the very first time, used to study the transition from zinc-ion batteries to zinc electrolytic batteries by the continuous addition of acetate ions. These complementary techniques operando trace the mass and the composition evolution. The observed formation and dissolution of zinc hydroxide sulfate (ZHS) and manganese oxides evince the effect of acetate ions on zinc-manganese batteries from an alternative perspective. Both the amount of acetate and the pH value have large impacts on the capacity and Coulombic efficiency of the MnO 2 electrode, and thus they should be optimized when constructing a full zinc-manganese battery with high rate capability and reversibility., (© 2023 Wiley-VCH GmbH.)

A series of new double fence porphyrin dyes bJS1-bJS3, with eight long alkoxyl chains attached to four β-phenyl groups, have been designed and synthesized. The single fence meso-substituted counterparts mJS1-mJS3 were also prepared as reference dyes. Dyes bJS1-bJS3 and mJS1-mJS3 exhibit power conversion efficiencies of 8.03-10.69 % and 2.33-6.69 %, respectively. Based on photovoltaic studies, the remarkable cell performance of double fence porphyrin sensitizers can be attributed to reduced dye aggregation and a decreased charge-recombination rate. Notably, porphyrins bJS2 and bJS3 exhibit better efficiency than the benchmark YD2-o-C8 (9.83 % in this work), demonstrating that the double fence structure is a promising design strategy for efficient porphyrin sensitizers in high-performance DSSCs., (© 2020 Wiley-VCH GmbH.)

Organic semiconductors demonstrate several advantages over conventional inorganic materials for novel electronic and optoelectronic applications, including molecularly tunable properties, flexibility, low-cost, and facile device integration. However, before organic semiconductors can be used for the next-generation devices, such as ultrafast photodetectors (PDs), it is necessary to develop new materials that feature both high mobility and ambient stability. Toward this goal, a highly stable PD based on the organic single crystal [PtBr 2 (5,5'-bis(CF 3 CH 2 OCH 2 )-2,2'-bpy)] (or "Pt complex (1o)") is demonstrated as the active semiconductor channel-a material that features a lamellar molecular structure and high-quality, intraligand charge transfer. Benefitting from its unique crystal structure, the Pt-complex (1o) device exhibits a field-effect mobility of ≈0.45 cm 2 V -1 s -1 without loss of significant performance under ambient conditions even after 40 days without encapsulation, as well as immersion in distilled water for a period of 24 h. Furthermore, the device features a maximum photoresponsivity of 1 × 10 3 A W -1 , a detectivity of 1.1 × 10 12 cm Hz 1/2 W -1 , and a record fast response/recovery time of 80/90 µs, which has never been previously achieved in other organic PDs. These findings strongly support and promote the use of the single-crystal Pt complex (1o) in next-generation organic optoelectronic devices., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Optical resonance formed inside a nanocavity resonator can trap light within the active region and hence enhance light absorption, effectively boosting device or material performance in applications of solar cells, photodetectors (PDs), and photocatalysts. Complementing conventional circular and spherical structures, a new type of multishelled spherical resonant strategy is presented. Due to the resonance-enhanced absorption by multiple convex shells, ZnO nanoshell PDs show improved optoelectronic performance and omnidirectional detection of light at different incidence angles and polarization. In addition, the response and recovery speeds of these devices are improved (0.8 and 0.7 ms, respectively) up to three orders of magnitude faster than in previous reports because of the existence of junction barriers between the nanoshells. The general design principles behind these hollow ZnO nanoshells pave a new way to improve the performance of sophisticated nanophotonic devices., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Organic-inorganic hybrid perovskite materials exhibit a variety of physical properties. Pronounced coupling between phonon, organic cations, and the inorganic framework suggest that these materials exhibit strong light-matter interactions. The photoinduced strain of CH 3 NH 3 PbBr 3 is investigated using high-resolution and contactless in situ Raman spectroscopy. Under illumination, the material exhibits large blue shifts in its Raman spectra that indicate significant structural deformations (i.e., photostriction). From these shifts, the photostrictive coefficient of CH 3 NH 3 PbBr 3 is calculated as 2.08 × 10 -8 m 2 W -1 at room temperature under visible light illumination. The significant photostriction of CH 3 NH 3 PbBr 3 is attributed to a combination of the photovoltaic effect and translational symmetry loss of the molecular configuration via strong translation-rotation coupling. Unlike CH 3 NH 3 PbI 3 , it is noted that the photostriction of CH 3 NH 3 PbBr 3 is extremely stable, demonstrating no signs of optical decay for at least 30 d. These results suggest the potential of CH 3 NH 3 PbBr 3 for applications in next-generation optical micro-electromechanical devices., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Semipolar {101¯1} InGaN quantum wells are grown on (001) Si substrates with an Al-free buffer and wafer-scale uniformity. The novel structure is achieved by a bottom-up nano-heteroepitaxy employing self-organized ZnO nanorods as the strain-relieving layer. This ZnO nanostructure unlocks the problems encountered by the conventional AlN-based buffer, which grows slowly and contaminates the growth chamber., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The preparation of sensitizers for dye-sensitized solar cells (DSSCs) represents an active area of research for both sustainability and renewable energy. Both Ru(II) and Os(II) metal sensitizers offer unique photophysical and electrochemical properties that arise from the intrinsic electronic properties, that is, the higher propensity to form the lower-energy metal-to-ligand charge-transfer (MLCT) transition, and their capability to support chelates with multiple carboxy groups, which serve as a bridge to the metal oxide and enable efficient injection of the photoelectron. Here we present an overview of the synthesis and testing of these metal sensitizers that bear functional azolate chelates (both pyrazolate and triazolate), which are capable of modifying the metal sensitizers in a systematic and beneficial manner. Basic principles of the molecular designs, the structural relationship to the photophysical and electrochemical properties, and performances of the as-fabricated DSSCs are highlighted. The success in the breakthrough of the synthetic protocols and potential applications might provide strong stimulus for the future development of technologies such as DSSCs, organic light-emitting diodes, solar water splitting, and so forth., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this paper, high electrocatalytic and wettable nitrogen-doped microwave-exfoliated graphene (N-MEG) nanosheets are used as Pt-free counter electrode (CE) for dye-sensitized solar cells (DSSCs). A low cost solution-based process is developed by using cyanamide (NH2 CN) at room temperature and normal pressure. The pyrrolic and pyridinic N atoms are doped into the carbon conjugated lattice to enhance electrocatalytic activity. N-MEG film having N-doping active sites and large porosity provides a wettable surface to facilitate electrolyte diffusion so that improves fill factor. Moreover, the control of the air exposure time after completing N-MEG film is found to be crucial to obtain a reliable N-MEG CE. A high DSSC efficiency up to 7.18% can be achieved based on N-MEG CE, which is nearly comparable to conventional Pt CE., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)