Searching for Natural Conductive Fibrous Structures via a Green Sustainable Approach Based on Jute Fibers and Silver Nanoparticles

Abstract

This paper provides new insights regarding jute fibers functionalization with silver nanoparticles (Ag NPs) with improved conductivity values and highlights the sustainability of the processes involved. These NPs were applied onto jute fabrics by two different sustainable methods: ultraviolet (UV) photoreduction and by using polyethylene glycol (PEG) as a reducing agent and stabilizer. Field Emission Scanning Electron Microscopy (FESEM) images demonstrated that the Ag NPs were incorporated on the jute fibers surface by the two different approaches, with sizes ranging from 70 to 100 nm. Diffuse reflectance spectra revealed the plasmon absorption band, corresponding to the formation of metallic Ag NPs, in all samples under study. Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) was used to characterize the obtained samples, demonstrating NPs adsorption to the surface of the fibers. The resistivity value obtained by the two-point probe method of the jute fabric without functionalization is about 1.5 × 10⁷ Ω·m, whereas, after NPs functionalization, it decreased almost 15,000 times, reaching a value of 1.0 × 10³ Ω·m. Further research work is being undertaken for improving these values, however, 1000 Ω·m of resistivity (conductivity = 0.001 S/m) is already a very reasonable value when compared with those obtained with other developed systems based on natural fibers. In summary, this work shows that the use of very simple methodologies enabled the functionalization of jute fibers with reasonable values of conductivity. This achievement has a huge potential for use in smart textile composites.

Keywords: PEG; UV photoreduction; electrical conductivity; jute fibers; natural fibers; silver nanoparticles.

Figure 1

(a,c) Image of the jute fabric without functionalization; (b,d) jute fabric functionalized with silver nanoparticles. (e) CIElab color coordinates values.

Figure 2

Graphic demonstrating the resistivity values dependence on the precursor concentration.

Figure 3

(a) Jute fabric impregnated with Ag⁰-PEG suspensions; (b) jute fabric with Ag⁰-PEG NPs; (c) CIElab color coordinates.

Figure 4

Dependence of the resistivity values on AgNO₃ concentration.

Figure 5

Absorption spectra of a PEG solution and of a solution with PEG-Ag NPs obtained using 0.1 M AgNO₃.

Figure 6

STEM micrographs of the Ag NPs-PEG solution with different magnifications: 5 µm and 500 nm.

Figure 7

Images of jute fabric impregnated with Ag NPs (sample JPG3) synthesized with PEG, with different magnifications: (a) 100 µm, (b,c) 20 µm, and (d) 10 µm. The (b,c) images are in topographic mode, and the Z1 area was used for the EDS analysis.

Figure 8

Chemical microanalysis of the jute fabric surface with Ag NPs (sample JPG3), EDS spectrum, and elemental composition.

Figure 9

Normalized GSDR spectra of the jute fabric with Ag NPs-PEG obtained using different AgNO₃ concentrations.

Figure 10

Normalized GSDR spectra of the jute fabric with Ag NPs using the UV photoreduction method and different AgNO₃ concentrations.

Figure 11

FESEM analysis of jute without NPs (a,c), and sample JUV2 (b,d,e,f) with different magnifications: (b) 100 µm, (d) 20 µm, (e) 10 µm, and (f) 2 µm. The (e,f) images are in topographic mode.

Figure 12

Chemical microanalysis of the jute fabric with Ag NPs obtained with the UV method, using JUV2 sample as example.

Figure 13

ATR-FTIR spectra of the jute fabric, sample JUV2, and JPG2.