Abstract Rare earth ions with d-f transitions (Ce3+, Eu2+) have emerged as promising candidates for electroluminescence applications due to their abundant emission spectra, high light conversion efficiency, and excellent stability. However, directly injecting charge into 4f orbitals remains a significant challenge, resulting in unsatisfied external quantum efficiency and high operating voltage in rare earth light-emitting diodes. Herein, we propose a scheme to solve the difficulty by utilizing the energy transfer process. X-ray photoelectron spectroscopy and transient absorption spectra suggest that the Cs3CeI6 luminescence process is primarily driven by the energy transfer from the I2-based self-trapped exciton to the Ce-based Frenkel exciton. Furthermore, energy transfer efficiency is largely improved by enhancing the spectra overlap between the self-trapped exciton emission and the Ce-based Frenkel exciton excitation. When implemented as an active layer in light-emitting diodes, they show the maximum brightness and external quantum efficiency of 1073 cd m−2 and 7.9%, respectively.

Printable mesoscopic perovskite solar cells (p‐MPSCs) show great potential for commercialization, but little research has been devoted to understanding the dynamics of photogenerated carriers in this type of cell, limiting their further performance improvements. Herein, two techniques with complementary time scales were used, namely transient absorption spectroscopy (TAS) and time‐resolved photoluminescence spectroscopy (TRPL), to quantify the processes of carrier recombination, diffusion, and extraction in p‐MPSCs. It is found that the carrier diffusion in mesoscopic samples should not be neglected at the time scale monitored by TRPL, and thus the diffusion‐recombination model is more suitable compared to the simplified carrier recombination model usually used in interpreting the data of TAS and TRPL. As a result, the calculated carrier diffusion length within the perovskite filled in the mesoscopic scaffold is up to 5.48 µm. This also demonstrates that the hole transport layer is not necessary for p‐MPSCs. In addition, the relationship between the maximum quasi‐Fermi energy level splitting and the bulk recombination coefficient within perovskite is determined through calculations. This study takes an important step toward establishing the relationship between the mesoscopic structure, carrier dynamics, and device performance of p‐MPSCs.

Balancing the stability and interfacial charge transfer (CT) ability of perovskite nanocrystals (PNCs) are the most challenging issue confronting their practical application in photoelectrochemistry (PEC) fields. Here, an efficient surface capping strategy is introduced relying on a set of air-stable nitroxide-based organic radical polymers with well-matched energy levels towards CsPbBr3 nanocrystals. The native ligand oleyl amine and oleic acid were readily replaced by radical polymers because of their high-affinity properties. The resulting radical polymer coated PNCs exhibit exceptional tolerance to water, thermal, and UV illumination with remarkable CT processes. The versatility and immense practical utility of such stable PNCs-radical core/shell structure are showcased by the halogen exchange between PNCs/radical and aryl chlorides at ambient temperature, demonstrating superb reduction ability of this complex. Besides, this strategy was also employed to improve the power conversion efficiency and stability of PNCs based solar cells. This approach imparts exceptional photoelectrochemical sta-bility and catalytic activity to the nanocrystals with excellent interfacial CT efficiency.

Traditional wound dressings mainly participate in the passive healing processes and are rarely engaged in active wound healing by stimulating skin cell behaviors. Electrical stimulation (ES) has been known to regulate skin cell behaviors. Herein, a series of multifunctional hydrogels based on regenerated bacterial cellulose (rBC) and MXene (Ti3 C2 Tx ) are first developed that can electrically modulate cell behaviors for active skin wound healing under external ES. The composite hydrogel with 2 wt% MXene (rBC/MXene-2%) exhibits the highest electrical conductivity and the best biocompatibility. Meanwhile, the rBC/MXene-2% hydrogel presents desired mechanical properties, favorable flexibility, good biodegradability, and high water-uptake capacity. An in vivo study using a rat full-thickness defect model reveals that this rBC/MXene hydrogel exhibits a better therapeutic effect than the commercial Tegaderm film. More importantly, in vitro and in vivo data demonstrate that coupling with ES, the hydrogel can significantly enhance the proliferation activity of NIH3T3 cells and accelerate the wound healing process, as compared to non-ES controls. This study suggests that the biodegradable and electroactive rBC/MXene hydrogel is an appealing candidate as a wound dressing for skin wound healing, while also providing an effective synergistic therapeutic strategy for accelerating wound repair process through coupling ES with the hydrogel dressing.

Filamentous fungi have several industrial, environmental, and medical applications. However, they are rarely utilized owing to the limited availability of full-genome sequences and genetic manipulation tools. Since the recent discovery of the full-genome sequences for certain industrially important filamentous fungi, CRISPR/Cas9 technology has drawn attention for the efficient development of engineered strains of filamentous fungi. CRISPR/Cas9 genome editing has been successfully applied to diverse filamentous fungi. In this review, we briefly discuss the use of common genetic transformation techniques as well as CRISPR/Cas9-based systems in filamentous fungi. Furthermore, we describe potential limitations and challenges in the practical application of genome engineering of filamentous fungi. Finally, we provide suggestions and highlight future research prospects in the area.

Urea-formaldehyde resin (UF) or phenolic resin (PF) is used widely as binder in the production of fiberboard, and formaldehyde emissions from UF or PF is seriously harmful for human health. Eco-friendly fiberboard was produced without binder using poplar wood shavings (PWS) bio-pretreated by white rot fungi Coriolus versicolor in this study, and the correlations between the metabolites and lignocellulose components and the bending strength (BS) of fiberboard were also studied. After PWS were pretreated by C versicolor for 21 days, the BS and water swelling ratio of the fiberboard were reached to 22.7 MPa and 12.4%, respectively. The soluble polysaccharide and reduce sugar in PWS were detected very low, which had a weak effect on the fiberboard. Lower content of hemicellulose and higher content of lignin were detected and beneficial to the BS of fiberboard. Manganese peroxidase was detected and had a lag enzymolysis effect. Laccase, lignin peroxidase and cellulase were not detected but laccase or cellulase might have a weak influence on fiberboard. The fiberboard production with this bio-pretreatment should be eco-friendly and eliminate the potential formaldehyde emission. (C) 2019 Elsevier Ltd. All rights reserved.