Biomass-derived carbon nanomaterials for sensor applications.

TL;DR: Researchers developed Ni1−xFeXS-biocarbon composites for high-performance lithium-ion batteries, enhancing cycle stability and rate capability through multilayered biocarbon nanosheet formation and Fe doping, achieving high discharge capacities and long-term stability.

Abstract: Abstract Carbon quantum dots (CQDs) are nanomaterials characterized by their optoelectronic properties, their fluorescent activity and their good electrical conductivity. In addition, due to their small size of between 1 and 10 nm, they can form mesoporous surfaces when impregnated in thin films of interest. These characteristics are why they were synthesized in this research, to help enhance electrochemical properties. For this, agro-industrial waste was used. In this research, we worked with cocoa bean husks (CBH), a biomass rich in lignocellulose. The biomass was subjected to pyrolysis at 350 °C for 6 h, from which a biochar was obtained that was subjected to ultrasonic exfoliation where the CQDs were finally obtained. Morphological characterizations were made using scanning electron microscopy, high resolution transmission electron microscopy and spectroscopic characterizations using energy dispersive spectroscopy, Fourier transform infrared spectroscopy, fluorescence spectroscopy, UV–vis spectroscopy. The results give a yield of 4.32 ± 0.08 % in a synthesis that can be considered green, considering that no polluting or expensive reagents were used, since agro-industrial waste or residues and water was used as a solvent. High resolution transmission electron microscopy imaging allowed a size of 2.6 ± 0.7 nm of the CQDs to be obtained, consistent with the blue–violet fluorescence that shows the nanoparticles in solution. This was also observed in fluorescence spectroscopy where the emission range is 408–450 nm. When the CQDs were impregnated in Ti and Pt-based electrocatalysts, they were shown to enhance their electrochemical response. This confirmed the hypothesis regarding the improvement of electrical and morphological properties to improve electrocatalytic reactions such as oxygen evolution reaction, hydrogen adsorption and desorption.

TL;DR: Researchers convert coconut shell waste into high-value graphitic activated carbon using a thermal graphitization method, achieving a high electrical conductivity of 148 µS, making it a promising, cost-effective, and eco-friendly material for carbon-based electrodes.

TL;DR: Upcycled carbon microtubes derived from used face masks decorated with bimetallic copper-cobalt nanoparticles are used to detect lead in wastewater.

TL;DR: Integrating conceptually similar models of the growth of marine and terrestrial primary producers yielded an estimated global net primary production of 104.9 petagrams of carbon per year, with roughly equal contributions from land and oceans.

TL;DR: Signalling roles for hydrogen peroxide during abscisic-acid-mediated stomatal closure, auxin-regulated root gravitropism and tolerance of oxygen deprivation are now evident.

TL;DR: It will be shown that HTC does not only access carbonaceous materials under comparatively mild hydrothermal conditions, but also replaces the more technical and structurally well-defined charring by a controlled chemical process, leading to very different morphologies with miscellaneous applications, including modern carbon nanocomposites and hybrids.

TL;DR: The strength and flexibility of carbon nanotubes make them of potential use in controlling other nanoscale structures, which suggests they will have a significant role in nanotechnology engineering.