Freestanding laser-induced two dimensional heterostructures for self-contained paper-based sensors

Abstract

The production of 2D/2D heterostructures (HTs) with favorable electrochemical features is challenging, particularly for semiconductor transition metal dichalcogenides (TMDs). In this work, we introduce a CO2 laser plotter-based technology for...

Laser-induced 2D/0D graphene-nanoceria freestanding paper-based films for on-site hydrogen peroxide monitoring in no-touch disinfection treatments

“…To obtain 2D/0D catalytic transferable nanostructured films, the CO 2 laser’s ability to induce GO conversion to conductive rGO and to drive, at the same time, the synthesis of nanoceria was initially explored. Since the synthesis has been never attempted using a CO 2 -laser, the amount of nanoceria precursor (Ce 3+ ) was studied, while the GO amount and laser parameters were set according to our previous studies [ 2 , 6 ]. GO and different amounts of Ce 3+ were co-filtered and the obtained films were treated with the laser.…”

“…To gain more information about the rGO-nCe film chemistry and structure, Raman spectra of GO, rGO, and rGO-nCe films were also recorded. Figure 3 C, showing the Raman spectra of rGO and rGO-nCe, the laser-induced GO reduction is confirmed by the relative D band decrease (1350.9 ± 1.9 cm −1 ) and 2D band appearance (2689.6 ± 1.0 cm −1 ), compared to the rGO only; these changes can be attributed to the sp 3 carbon/oxygen-containing groups removal with the following restoration of sp 2 domains and the exfoliation/bidimensional structural rearrangement [ 2 , 6 ]. In particular, the GO possesses the highest I D /I G ratio (0.88 ± 0.05), while the lowest value was observed for the rGO (I D /I G = 0.45 ± 0.03), confirming the rise of the sp 2 carbon domain.…”

“…Benchtop laser-based technologies have been increasingly used for NMs patterning, structuring, and property-boosting ability toward carbonaceous and metal substrates/materials; they take advantage of the photothermal energy released by the laser IR emission which, in the case of photosensitive substrates, leads to instantaneous morpho-chemical changes [ 2 , 3 ]. IR-laser plotters have been employed to produce graphene-like and graphitized surfaces/structures, directly treated with laser carbon-containing substrates [ 4 ].…”