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A new and simple strategy towards electric‐field‐driven multiple chirality switching device has been designed and fabricated by combining a newly synthesized base‐responsive chiroptical polymer switch (R‐FLMA) and p‐benzoquinone (p‐BQ) via proton‐coupled electron transfer (PCET) mechanism. Clear and stable triple chirality states (silence, positive, negative) of this device in visible band can be regulated reversibly (>1000 cycles) by adjusting voltage programs. Furthermore, such chiral switching phenomena are also accompanied by apparent changes of color and fluorescence. More importantly, the potential application of this device for a spatial light modulator has also been demonstrated. [ABSTRACT FROM AUTHOR]

Electrofluorochromic (EFC) materials and devices with controllable fluorescence properties show great application potential in advanced anticounterfeiting, information storage and display. However, the low color purity caused by the broad emission spectra and underperforming switching time of the existing EFC materials limit their application. Through biomimetic exploration and the study of reversible electrochemical responsive coordination reactions, boron-nitrogen embedded polyaromatics (B,N-PAHs) with narrow-band emission and high color purity have been successfully integrated into EFC systems, which also help to better understand the role of boron in biological activity. The EFC device achieve good performance containing quenching efficiency greater than 90% within short switching time (t on : 0.6 s, t off : 2.4 s), and nearly no performance change after 200 cycles test. Three primary color (red, green, and blue) EFC devices are successfully prepared. In addition, new phenomena are obtained and discussed in this biomimetic exploration of related boron reactions. The success and harvest of this exploration are expected to provide new ideas for optimizing properties and broadening applications of EFC materials. Moreover, it may provide ideas and reference significance for further exploring and understanding the function of boron compounds in biological systems., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Considering the alarming frequency of coal mine gas disasters globally, there is an urgent need to develop efficient gas control technologies to ensure mining safety. This study focuses on the problem of high peak gas emission restriction in the process of coal roadway tunneling in outburst coal seams, taking the No. 15 outburst coal seam of the Pingshu Coal Mine as the research object. Based on coal sample testing analysis and the application of CO 2 gas fracturing (CO 2 -Frac) in coal mines, a comprehensive evaluation was conducted on pore-fracture structure alteration and homogenization gas emission effect induced by CO 2 -Frac, providing technical solutions for coal mine safety production. The results are as follows: (1) CO 2 -Frac induces fracture propagation and the development of three types of fracture structures: Tri-Wing Fracture, Damage Markers, and Coal Matrix Fragmentation. (2) Following CO 2 -Frac at 150 MPa, the pore volume and average diameter of pores in the 100-10,000 nm range increased by 128% and 61%, respectively, compared to the pre-CO 2 -Frac state. (3) During the excavation period, continuous monitoring of the airflow for 3 days showed a significant homogenization of gas emission, with a maximum value of 0.450% and a variance value of 0.0031, indicating a reduction of 31% and 68%, respectively. These results reveal several key findings: The pore-fracture structure alteration enhances gas diffusion and permeation, providing high-speed pathways for gas migration, resulting in a substantial increase in gas extraction efficiency. During coal cutting, the modified coal exhibits homogenized gas emission, eliminating the high peak phenomenon and achieving safe and efficient mining. These findings demonstrate that CO 2 -Frac has broad potential in gas emission homogenization for widespread application in coal mines with similar gas geological conditions., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

A new and simple strategy towards electric-field-driven multiple chirality switching device has been designed and fabricated by combining a newly synthesized base-responsive chiroptical polymer switch (R-FLMA) and p-benzoquinone (p-BQ) via proton-coupled electron transfer (PCET) mechanism. Clear and stable triple chirality states (silence, positive, negative) of this device in visible band can be regulated reversibly (>1000 cycles) by adjusting voltage programs. Furthermore, such chiral switching phenomena are also accompanied by apparent changes of color and fluorescence. More importantly, the potential application of this device for a spatial light modulator has also been demonstrated., (© 2020 Wiley-VCH GmbH.)