Dual-functional lignocellulosic mulch as agricultural plastic alternative for sustained-release of photosensitive pesticide and immobilizing heavy metal ions.

The extensive utilization of non-biodegradable plastic agricultural mulch in the past few decades has resulted in severe environmental pollution and a decline in soil fertility. The present study involves the fabrication of environmentally friendly paper-based mulch with dual functionality, incorporating agrochemicals and heavy metal ligands, through a sustainable papermaking/coating technique. The functional paper-based mulch consists of a cellulose fiber web incorporated with Emamectin Benzoate (EB)@ Aminated sodium lignosulfonate (ASL). The spherical microcapsules loaded with the pesticide EB exhibited an optimal core-shell structure for enhanced protection and controlled release of the photosensitizer EB (Sustained release >75 % in 50 h). Meanwhile, the ASL, enriched with metal chelating groups (-COOH, -OH, and -NH2, etc.), served as a stabilizing agent for heavy metal ions, enhancing soil remediation efficiency. The performance of paper-based mulch was enhanced by the application of a hydrophobic layer composed of natural chitosan/carnauba wax, resulting in exceptional characteristics such as superior tensile strength, hydrophobicity, heat insulation, moisture retention, as well as compostability and biodegradability (biodegradation >80 % after 70 days). This study developed a revolutionary lignocellulosic eco-friendly mulch that enables controlled agrochemical release and soil heavy metal remediation, leading to a superior substitute to conventional and non-biodegradable plastic mulch used in agriculture.

Deep eutectic supramolecular polymer functionalized MXene for enhancing mechanical properties, photothermal conversion, and bacterial inactivation of cellulose textiles.

Two-dimensional (2D) transition metal carbides (Ti3C2Tx MXene) have gained significant attention for their potential in constructing diverse functional materials, However, MXene is easily oxidized and weakly bound to the cellulose matrix, which pose challenges in developing MXene-decorated non-woven fabric with strong bonding and stable thermal management properties. Herein, we successfully prepared deep eutectic supramolecular polymer (DESP) functionalized MXene to address these issues. MXene can be wrapped with DESP to be insulated from water and protected from being oxidized. Subsequently, we achieved an efficient in-situ deposition of DESP-functionalized MXene onto fibers through a combination of dip coating and photopolymerization technique. The resulting nonwoven fabric (CNs-DESP@M) exhibited excellent photothermal conversion properties along with rapid thermal response and functional stability. Interestingly, the interface bonding between MXene and the fiber surface was significantly enhanced due to the abundant pyrogallol groups in DESP, resulting in the composite textile exhibiting commendable mechanical properties (2.68 MPa). Moreover, the as-prepared textile demonstrates outstanding bactericidal efficacy against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The multifunctional textile, created through a facile and efficient approach, demonstrates remarkable potential for applications in smart textiles, catering to the diverse needs of individuals in the future.

Organic-inorganic hybrid ZIF-8/MXene/cellulose-based textiles with improved antibacterial and electromagnetic interference shielding performance.

Despite the tremendous efforts on developing antibacterial wearable textile materials containing Ti3C2Tx MXene, the singular antimicrobial mechanism, poor antibacterial durability, and oxidation susceptibility of MXene limits their applications. In this context, flexible multifunctional cellulosic textiles were prepared via layer-by-layer assembly of MXene and the in-situ synthesis of zeolitic imidazolate framework-8 (ZIF-8). Specifically, the introduction of highly conductive MXene enhanced the interface interactions between the ZIF-8 layer and cellulose fibers, endowing the green-based materials with outstanding synergistic photothermal/photodynamic therapy (PTT/PDT) activity and adjustable electromagnetic interference (EMI) shielding performance. In-situ polymerization formed a MXene/ZIF-8 bilayer structure, promoting the generation of reactive oxygen species (ROS) while protecting MXene from oxidation. The as-prepared smart textile exhibited excellent bactericidal efficacy of >99.99 % against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) after 5 min of NIR (300 mW cm-2) irradiation which is below the maximum permissible exposure (MPE) limit. The sustained released Zn2+ from the ZIF-8 layer achieved a bactericidal efficiency of over 99.99 % within 48 h without NIR light. Furthermore, this smart textile also demonstrated remarkable EMI shielding efficiency (47.7 dB). Clearly, this study provides an elaborate strategy for designing and constructing multifunctional cellulose-based materials for a variety of applications.

Coumarin-Modified Graphene Quantum Dots as a Sensing Platform for Multicomponent Detection and Its Applications in Fruits and Living Cells.

In this work, coumarin derivatives (C) are used to enhance the fluorescence of graphene quantum dots (GQDs) by covalently linking the carboxyl groups on the edge of the GQD sheet. The as-synthesized coumarin-modified graphene quantum dots (C-GQDs) have a uniform particle size with an average diameter of 3.6 nm. Simultaneously, the C-GQDs have strong fluorescence emission, excellent photostability, and high fluorescence quantum yield. C-GQDs and CN- can form a C-GQDs+CN- system due to deprotonation and/or intermolecular interactions. The introduced hydroquinone (HQ) is oxidized to benzoquinone (BQ), and the interaction between BQ and the C-GQDs+CN- system could lead to fluorescence enhancement of C-GQDs. Meanwhile, the redox reaction between BQ and ascorbic acid (AA) can be used for quantitative detection of AA with CN- and HQ being used as substrates. Based on the above mechanism, C-GQDs are developed as a multicomponent detection and sensing platform, and the detection limits for CN-, HQ, and AA were 4.7, 2.2, and 2.2 nM, respectively. More importantly, satisfactory results were obtained when the platform was used to detect CN-, HQ, and AA in living cells and fresh fruits.

Two isomeric and distinguishable H2S fluorescence probes for monitoring spoilage of eggs and visualizing exogenous and endogenous H2S in living cells.

Accurate fabrication of fluorescence probes to efficiently monitor and detect H2S levels in the fields of foodstuffs and physiology is crucial. Herein, we report two isomeric phenanthro[9,10-d]imidazole benzene sulfonamide-derived fluorescence probes (PI-2-SA and PI-4-SA), both of which display remarkable responses toward H2S over other analytes. The spectral characteristics of the two probes were investigated and are discussed in detail. By comparison, PI-2-SA was specific, sensitive (the limit of detection was ca. 12.3 nM), rapid (within ≤3 min) and dynamic (the rate constant was 0.02 s-1). Significantly, PI-2-SA was proved to be effective in monitoring the shelf-time progress of egg samples in real time as well as in the imaging of exogenous and endogenous H2S in HeLa cells.