Embellishing 2-D MoS₂ Nanosheets on Lotus Thread Devices for Enhanced Hydrophobicity and Antimicrobial Activity

Abstract

Herein, we report cellulose-based threads from Indian sacred Lotus ( Nelumbo nucifera ) of the Nymphaceae family embellished with MoS 2 nanosheets for its enhanced hydrophobic and antimicrobial properties. MoS 2 nanosheets synthesized by a coprecipitation method using sodium molybdate dihydrate (Na 2 MoO 4 ·2H 2 O) and thioacetamide (CH 3 CSNH 2 ) were used as a sourse for MoS 2 particle growth with cellulose threads extracted from lotus peduncles. The size, crystallinity, and morphology of pure and MoS 2 -coated fibers were studied using X-ray diffractometry (XRD) and scanning electron microscopy (SEM). the XRD pattern of pure lotus threads showed a semicrystalline nature, and the threads@MoS 2 composite showed more crystallinity than the pure threads. SEM depicts that pure lotus threads possess a smooth surface, and the MoS 2 nanosheets growth can be easily identified on the threads@MoS 2 . Further, the presence of MoS 2 nanosheets on threads was confirmed with EDX elemental analysis. Antimicrobial studies with Escherichia coli and Candida albicans reveal that threads@MoS 2 have better resistance than its counterpart, i.e., pure threads. MoS 2 sheets play a predominant role in restricting the wicking capability of the pure threads due to their enhanced hydrophobic property. The water absorbency assay denotes the absorption rate of threads@MoS 2 to 80%, and threads@MoS 2 shows no penetration for the observed 60 min, thus confirming its wicking restriction. The contact angle for threads@MoS 2 is 128°, indicating its improved hydrophobicity.

Prospective applications of two-dimensional materials beyond laboratory frontiers: A review

“…The twisted ribbon like structure of the material ( Figure 9 E) helps in enhancing the permeability and moisture absorption. MoS 2 coating on the fiber helps in enhancing the superhydrophobic behavior as shown in Figure 9 F. 190 In general, nanoblade effect is observed in composites with 2D materials like MXene as shown in Figure 9 G, where the stress is mediated by the contact of highly sharp edges. Moreover, the ROS (Reactive Oxygen Species) effect coupled with MXene also plays a vital role in enhancing the antimicrobial activity.…”

“…Flow cytometry dot plots of E. coli (A and B) and B. subtilis (C and D) bacterial cells exposed to control PVDF (a and b) and MXene films (C and D) for 24 h reproduced with permission from Nature. 189 (E) SEM image of MoS 2 -coated lotus fiber, 190 (reproduced with permission from American Chemical Society). (F and G) Contact angle of pure and MoS 2 -coated fiber and (G) Schematic diagram of antibacterial activity in PP/Ti 3 C 2 T x nanocomposites showing the synergistic physical nanoblade effect and ROS generation 191 (reproduced with permission from American Chemical Society).…”

“… (E) SEM image of MoS 2 -coated lotus fiber, 190 (reproduced with permission from American Chemical Society). …”

Smart Bags and Smartphone for On-The-Spot Detection of Bleached Garlic

“…To address the above issues, cellulose-based devices have garnered a significant amount of attention over the past few decades (Mani et al 2019;Prabhu et al 2020b;Hasandka et al 2021;Prabhu et al 2021;Kelkar et al 2022). Recent developments in cellulose-based microfluidics have significantly helped to identify adulterants, pathogens, and other analytes in a cost-effective way (Prabhu et al 2020a;Mani et al 2020;Hasandka et al 2022;Ray et al 2022a;Selvam et al 2022), without the need for sophisticated techniques and with exploration of different methods for sensitivity enhancement (Mani et al 2013;Sudarsan et al 2023aSudarsan et al , 2023b. Herein, frugal devices are made from paper or other porous materials (such as threads), that manipulate small (10 −6 to 10 −9 L) volumes of fluids by capillary action (Nishat et al 2021;Ray et al 2022b).…”