## 2 Materials and Methods  
Molybdenum disulfide (MoS\({}_{2}\)) nanosheets were grown on cellulose paper substrates by a microwave-assisted hydrothermal method optimizing the hydrothermal temperature and reaction time. Sodium molybdate dihydrate (Na\({}_{2}\)MoO\({}_{4}\).2H\({}_{2}\)O) and thiourea (CS(NH\({}_{2}\))\({}_{2}\)) were used as precursors of molybdenum and sulfur, respectively. Cellulose paper was used as a substrate, which was previously washed by sonication in deionized water and by acetone and isopropyl alcohol, both for 15 min. For direct growth on the cellulose fibers, the substrates were previously immersed in a seed solution composed of sodium molybate and thiourea (1:4) for 60 min. After that time, the substrates were dried on a hotplate at 80 \({}^{\circ}\)C for 60 min. Substrates with deposited seeds were placed in a hydrothermal reactor with nutrition solution also composed of sodium molybate and thiourea (1:4). Then, they were taken to the microwave oven for synthesis that was carried out with a power of 100 W, maximum pressure of 280 psi, and with different values of temperature and time of synthesis. Three different synthesis temperatures were used: 190 \({}^{\circ}\)C, 200 \({}^{\circ}\)C, and 220 \({}^{\circ}\)C. These were chosen to apply the shortest possible time for the growth of the nanostructures, corresponding to each temperature used, until the maximum time of 120 min. Thus, the different temperatures and synthesis times used were: 190 \({}^{\circ}\)C for 30, 45 and 120 min, 200 \({}^{\circ}\)C for 15, 30, 45, 60 and 120 min, 220 \({}^{\circ}\)C for 05, 15, 30, 45, 60, and 120 min. After the growth of the MoS\({}_{2}\) on the cellulose fibers, the paper with the grown nanostructures were washed with ethanol in ultrasound for 15 min to remove the nanostructures not fixed on the sample's surface. Finally, the samples were dried in a nitrogen flow. Interdigital contacts were deposited by the screen-printing technique using commercial conductive ink CRSN2442 Suntronic, composed of silver nanoparticles dispersed on the solvent (solvent-based), acquired from Coats Screen Inks GmbH. The interdigital electrodes have a total dimension of 10.0 \(\times\) 6.0 mm, 500 \(\upmu\)m electrode wide and a 500 \(\upmu\)m active channel between the electrodes. Structural and optical properties of the MoS\({}_{2}\) nanostructures, grown on cellulose paper substrate, were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and micro-Raman spectroscopy. The crystal phase was obtained by X-ray diffraction (X'Pert PRO MPD), using Cu-k\(\alpha\) radiation (\(\uplambda=1.540598\) A). The XRD patterns were collected in symmetric configuration in the 20 range of 5\(-\)70\({}^{\circ}\), using a step angle of 0.05\({}^{\circ}\), step time of 2 s, operating at 40 kV tension and 30 mA current. The morphology was studied by scanning electron microscopy (Carl Zeiss AURIGA CrossBeam workstation). Raman measurements were performed in a Renishaw inVia Reflex micro-Raman spectrometer equipped with an air-cooled CCD detector and a HeNe laser operating at 50 mW of 532 nm laser excitation. The spectral resolution of the spectroscopic system is 0.3 cm\({}^{-1}\). The laser beam was focused with a 50 \(\times\) Leica objective lens (N Plan EPI) with a numerical aperture of 0.75. An integration time of 3 scans of 1.5 s each was used for all single-scan measurements to reduce the random background noise induced by the detector, without significantly increasing the acquisition time. The intensity of the incident laser was 2.5 mW. Triplicates were taken for all spectra. The spectrograph was calibrated between different Raman sessions using the Raman line at 521 cm\({}^{-1}\) of an internal Si wafer for reducing possible fluctuations of the Raman system. All spectra were recorded at room temperature. Raw data were collected digitally with the Wire 5.0 software for processing.