Graphene oxide (GO) possesses specific properties that are revolutionizing materials science, with applications extending from flexible electronics to advanced nanotechnology. A key method for harnessing GO's potential is its laser-induced reduction, yet the exact mechanisms - photothermal versus photochemical effects - remain unclear. Herein, we discover the dominant role of photochemical reactions in the laser reduction of GO under visible light, challenging the prevailing assumption that photothermal effects are dominant.
View Article and Find Full Text PDFGrowing concerns about pesticide residues in agriculture are pushing the scientific community to develop innovative and efficient methods for detecting these substances at low concentrations down to the molecular level. In this context, surface-enhanced Raman spectroscopy (SERS) is a powerful analytical method that has so far already undergone some validation for its effectiveness in pesticide detection. However, despite its great potential, SERS faces significant difficulties obtaining reproducible and accurate pesticide spectra, particularly for some of the most widely used pesticides, such as malathion, chlorpyrifos, and imidacloprid.
View Article and Find Full Text PDFWhile most of the research in graphene-based materials seeks high electroactive surface area and ion intercalation, here, we show an alternative electrochemical behavior that leverages graphene's potential in biosensing. We report a novel approach to fabricate graphene/polymer nanocomposites with near-record conductivity levels of 45 Ω sq and enhanced biocompatibility. This is realized by laser processing of graphene oxide in a sandwich structure with a thin (100 μm) polyethylene terephthalate film on a textile substrate.
View Article and Find Full Text PDFFlexible electronics have sparked significant interest in the development of electrically conductive polymer-based composite materials. While efforts are being made to fabricate these composites through laser integration techniques, a versatile methodology applicable to a broad range of thermoplastic polymers remains elusive. Moreover, the underlying mechanisms driving the formation of such composites are not thoroughly understood.
View Article and Find Full Text PDFThis study investigates the effects of high-power laser irradiation on multilayer MoS, a promising material for catalysis, optoelectronics, and energy applications. In addition to previously reported sculpting of MoS layers, we discovered a novel effect of laser-induced photothermal heating that drives the chemical activation of MoS. The photothermal effect was confirmed by temperature-dependent experiments, in situ temperature measurements with nanolocalized probes, and simulations.
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