Search

Organic electrode materials are gaining increased attention in energy storage applications, but often encounter challenges such as low capacity and poor cycling stability. This paper explores the utilization of a 1‐D coordination polymer, copper(II)‐2,5‐dihydroxy‐1,4‐benzoquinone (Cu‐DHBQ), as a cathode material for Li‐ion batteries for the first time. Cu‐DHBQ is air‐stable, devoid of coordinated water molecules, and possesses a high theoretical capacity of 266 mAh g−1. With an optimal sodium alginate (SA) binder content of 25 wt%, the Cu‐DHBQ cathode demonstrates a notable initial capacity of 214 mAh g−1 and outstanding cycling stability, retaining 210 mAh g−1 (98% capacity retention) after 200 cycles at a current rate of 100 mA g−1. A comprehensive investigation into the capacity fading mechanisms, the bonding capability of the SA binder, and the interactions between Cu‐DHBQ and SA is conducted using scanning electron microscope (SEM), peel tests, and Fourier transform infrared spectroscopy (FTIR), respectively. Additionally, the electrochemical reaction mechanisms of Cu‐DHBQ are examined using ex situ X‐ray photoelectron spectroscopy (XPS) and FTIR. These findings offer valuable insights into understanding the electrochemical properties of coordination polymers and metal‐organic frameworks based on DHBQ, shedding light on their potential as materials for battery electrodes. [ABSTRACT FROM AUTHOR]

Conjugated polymers with tailorable composition and microarchitecture are propitious for modulating catalytic properties and deciphering inherent structure‐performance relationships. Herein, we report a facile linker engineering strategy to manipulate the electronic states of metallophthalocyanine conjugated polymers and uncover the vital role of organic linkers in facilitating electrocatalytic oxygen reduction reaction (ORR). Specifically, a set of cobalt phthalocyanine conjugated polymers (CoPc‐CPs) wrapped onto carbon nanotubes (denoted CNTs@CoPc‐CPs) are judiciously crafted via in situ assembling square‐planar cobalt tetraaminophthalocyanine (CoPc(NH2)4) with different linear aromatic dialdehyde‐based organic linkers in the presence of CNTs. Intriguingly, upon varying the electronic characteristic of organic linkers from terephthalaldehyde (TA) to 2,5‐thiophenedicarboxaldehyde (TDA) and then to thieno/thiophene‐2,5‐dicarboxaldehyde (bTDA), their corresponding CNTs@CoPc‐CPs exhibit gradually improved electrocatalytic ORR performance. More importantly, theoretical calculations reveal that the charge transfer from CoPc units to electron‐withdrawing linkers (i.e. TDA and bTDA) drives the delocalization of Co d‐orbital electrons, thereby downshifting the Co d‐band energy level. Accordingly, the active Co centers with more positive valence state exhibit optimized binding energy toward ORR‐relevant intermediates and thus a balanced adsorption/desorption pathway that endows significant enhancement in electrocatalytic ORR. This work demonstrates a molecular‐level engineering route for rationally designing efficient polymer catalysts and gaining insightful understanding of electrocatalytic mechanisms. [ABSTRACT FROM AUTHOR]

Cyano‐containing electrodes usually promise high theoretical potentials while suffering from uncontrollable self‐dissolution and sluggish reaction kinetics. Herein, to remedy their limitations, an unprecedented core–shell heterostructured electrode of carbon nanotubes encapsulated in poly(1,4‐dicyanoperfluorobenzene sulfide) (CNT@PFDCB) is rationally crafted via molecule and microstructure modulations. Specifically, the linkage of sulfide bridges of PFDCB prevents the active cyano groups from dissolving, resulting in a robust structure. The fluorinations modulate the electronic configurations in frontier orbitals, allowing higher electrical conductivity and elevated output voltage. Combined with the core–shell architecture to unlock the sluggish diffusion kinetics for both electrons and guest ions, the CNT@PFDCB exhibits an impressive capacity (203.5 mAh g−1), remarkable rate ability (127.6 mAh g−1 at 3.0 A g−1), and exceptional cycling stability (retaining 81.1 % capacity after 3000 cycles at 1.0 A g−1). Additionally, the Li‐storage mechanisms regarding PFDCB are thoroughly revealed by in situ attenuated total reflection infrared spectroscopy, in situ Raman spectroscopy, and theoretical simulations, which involve the coordination interaction between Li ions and cyano groups and the electron delocalization along the conjugated skeleton. More importantly, a practical fully organic cell based on the CNT@PFDCB is well‐validated that demonstrates a tremendous potential of cyanopolymer as the cathode to replace its inorganic counterparts. [ABSTRACT FROM AUTHOR]

Smoke tree (Cotinus coggygria) is an important ornamental tree that represents the autumnal landscape of red leaves in Northern China, especially in Beijing. However, Verticillium wilt, caused by the fungus (Verticillium dahliae), has resulted in a high mortality rate for smoke trees, posing a serious threat to the highly valued landscape of red leaves in Beijing. To explore an efficient control measure for Verticillium wilt, we systematically analyzed the applicability and efficacy of multiple treatments for three consecutive years in Xiangshan Park and Badaling Forest Park. From 2021 to 2023, diseased smoke trees in Xiangshan Park were subjected to three application methods (agent irrigation, trunk injection, or a combination of the two) and five candidate agents, namely Bacillus subtilis, azoxystrobin, propiconazole, carbendazim, and prochloraz. Analyses of the data for three consecutive years revealed a decreasing trend in the annual disease incidence rate. Specifically, the combined application of agent irrigation and trunk injection exhibited the highest control effect and a significant improvement in the landscape of red leaves in Beijing. Furthermore, the combination of propiconazole via irrigation plus the trunk injection of carbendazim and prochloraz had the greatest control effect. These suppressive measurements were further used and demonstrated to be effective in Badaling Forest Park. Overall, our study provides an effective disease management means for controlling Verticillium wilt in smoke trees. [ABSTRACT FROM AUTHOR]

BACKGROUND: Verticillium dahliae is a soil‐borne pathogenic fungus that causes Verticillium wilt disease on more than 400 plant species worldwide. Because of its broad host range and its ability to survive long term in the soil, there are few effective control measures for V. dahliae once it has become established. Accurate, sensitive, and rapid detection of V. dahliae is crucial for limiting pathogen entry into new regional environments and early management of Verticillium wilt. RESULTS: In this study, we developed a method to detect V. dahliae based on recombinase polymerase amplification (RPA) and CRISPR/Cas technology and used fluorescence and lateral flow test strips to monitor the outcomes. Through the establishment and optimization of RPA–CRISPR/Cas13a detection, the sensitivity of the fluorescence method was 1 am for genomic DNA (gDNA) within 20 min, whereas the sensitivity of the lateral flow strip method was 100 am for gDNA in 30 min. The field applicability of RPA–CRISPR/Cas13a was also validated by the detection of V. dahliae on smoke trees (Cotinus coggygria) in Xiangshan Park, Beijing, China. Finally, diplex detection for defoliating and nondefoliating pathotypes of V. dahliae was established by combining CRISPR–Cas12a/Cas13a with specific target genes. CONCLUSION: Taken together, this study achieved rapid, sensitive, and accurate detection of V. dahliae and the differentiation of defoliating and nondefoliating pathotypes and provides potential for field‐deployable diagnostic tools for rapid and ultrasensitive detection. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]