Carbon exhibits a variety of allotropes in different physical states, benefiting from its chemical valence capacity to generate a wide range of structures. A new twodimensional carbon allotrope, pentagraphene (PG-yne), was recently introduced in a theoretical study. This unique structure is derived from pentagraphene by incorporating acetylenic bonds between sp2 and sp3 hybridized carbon atoms. In the same study, it is predicted that pentagraphyne is capable of withstanding temperatures as high as 1000 K, and bandgap of 1.0 eV. Although its electronic and structural properties have been reported in the literature, its mechanical properties have not yet been studied, both in its monolayer form and in nanotubes, covering different chiralities and diameters, and this work aims to fill this gap in the literature. Accordingly, fully atomistic reactive molecular dynamics simulations were conducted using the ReaxFF (Reactive Force Field) potential for this study. In this perspective, the results indicate that the Young's modulus of PG-ene monolayers is approximately 51 GPa at room temperature, while for nanotubes, regardless of their chirality, it is around 45 GPa. Furthermore, it was observed that PG-ene-based systems exhibit an extensive and relatively flat plastic region before reaching the point of total fracture (critical strain), both for uniand bidimensional cases. Regarding thermal properties, a melting point at approximately 3600 K was identified, accompanied by a phase transition around 1100 K.

Throughout this research, the synthesis of Carbon Quantum Dots (CQDs) was carried out using Peat as a precursor. The microstructure and morphology of the precursor and nanomaterial were analyzed using X-ray Diffraction, Fourier Transform Infrared Spectroscopy (FTIR), UV-Vis Spectroscopy, Photoluminescence Spectroscopy (FL), and Transmission Electron Microscopy of High Resolution (HRTEM). Quantum dots were deposited on a gold/Optical Glass BK7 substrate using the SpinCoating technique in order to use it as a sensory device based on Surface Plasmonic Resonance (SPR). The setup adopted for the elaboration of the experimental apparatus was the Kretschmann configuration. Next, the Reflection Intensity curves were generated as a function of the Incidence Angle characteristic of the device, called SPR curves. The same curves were also generated for the devices in the presence of ammonia. In the same way, the SPR curves were generated, with and without ammonia, for the device with CQDs deposition, and the graphs were then compared. From this comparison, it was possible to observe an improvement in the sensor response with CQDs when exposed to the analyte.

The preservation of the environment has been increasingly discussed and addressed in
global news. It is crucial to detect contaminants in water bodies, such as metal ions and
herbicides, due to their toxic and non-biodegradable nature, which can cause serious damage to
the ecosystem. The overall objective of this study is to synthesize photoluminescent green
carbon quantum dots (G-CQDs) from peat. Peat is a type of organic soil formed by the partial
decomposition of plant material under wet and acidic conditions. In addition to its applications
as a gardening material, it is recognized for its carbon content. The synthesized G-CQDs will
be used as sensors for nickel 2+

, copper 2+, and Atrazine, which are commonly found in water.
The study focuses on low-temperature hydrothermal synthesis using the top-down method and
peat as a bioprecursor to obtain G-CQDs, employing UV-Visible absorption spectroscopy and
spectrofluorometry as analytical tools. The lowest detected concentration of Atrazine was 0.125
ppb, while the lowest detected concentrations of nickel 2+ and copper 2+ were 25 ppm. The
developed sensor proved to be highly efficient in detecting traces of these compounds in
contaminated water samples, making a significant contribution to environmental monitoring
and preservation. This work proposes a promising approach for the detection of contaminants
in water, providing an environmentally friendly and effective alternative for environmental
monitoring. Furthermore, the synthesis of G-CQDs from peat may open up new possibilities
for the sustainable use of natural resources

The main characteristic of this work is to provide an overview of carbon anoparticles or C-dots and their potential applicability, especially in agriculture. Demonstrating various synthetic routes and characteristics of these arbonaceous compounds, such as structure and attributesrelated to hotoluminescence, make them promising materials for various ds.Spectroscopic approaches to these new carbon-based materials show their enormous importance for replacing products that have a high capacity for damage, such as toxicity. The use of techniques such as Fourier transform infrared (FTIR) and ultraviolet (Uv-Vis) spectroscopy demonstrate that these nanocomposites have abundant functional groups, which can make these nanoparticles unique tools.Analyzing the main synthetic strategies, demonstrating top-down and bottom-up systems, is essential for the production of technologies that contribute to the preservation of the environment and have the prospect of bringing something new and sustainable to the next generations.With the collaboration of the startup Krilltech in providing Carbon Dots called Arbolina, it was possible to carry out a brief analysis of its structure and demonstrate its applicability in agriculture, cotton cultivation, in addition to real gains for the farmer.