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Two‐dimensional nanomaterials, such as graphene, transition metal dichalcogenides, MXenes, and other layered compounds, are the subject of intense theoretical and experimental research for applications in a wide range of advanced technological solutions, given their outstanding physical, chemical, and mechanical properties. In the context of food science and technology, their contributions are starting to appear, based on the advantages that two‐dimensional nanostructures offer to agricultural‑ and food‐related key topics, such as sustainable water use, nano‐agrochemicals, novel nanosensing devices, and smart packaging technologies. These application categories facilitate the grasping of the current and potential uses of such advanced nanomaterials in the field, backed by their advantageous physical, chemical, and structural properties. Developments for water cleaning and reuse, efficient nanofertilizers and pesticides, ultrasensitive sensors for food contamination, and intelligent nanoelectronic disposable food packages are among the most promising application examples reviewed here and demonstrate the tremendous impact that further developments would have in the area as the fundamental and applied research of two‐dimensional nanostructures continues. We expect this work will contribute to a better understanding of the promising characteristics of two‐dimensional nanomaterials that could be used for the design of novel and feasible solutions in the agriculture and food areas. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This work examines the physical and chemical interactions between the polar and nonpolar solvents and the surface of the MCM‐41 material, which serves as the isolating layer, employing sensing capacitance‐voltage measurements with a Metal‐Insulator‐Semiconductor (MIS) capacitor. It was observed that the MCM‐41 surface is more sensitive to methanol, which is a protic solvent, than to other nonpolar solvents like chloroform, according to the data. Furthermore, by analyzing the interaction of the methanol with the surface of MCM‐41 as a function of the applied field, the electron transfer, and the orientation of the solvent molecule, DFT Calculations using the Siesta simulation software enable us to assess this sensitivity. Based on the performance of MCM‐41 as the insulator in the MIS capacitor, MCM‐41 has a strong potential for the creation of high‐sensitivity sensors for solvent detection avoiding the functionalization process. [ABSTRACT FROM AUTHOR]

Using first‐principles density functional theory calculations, 1D armchair graphene nanoribbons (AGNRs) and graphene with an extended line defect (ELD) mimicking a grain boundary (GB) are investigated. Two AGNRs with n and m indices are laterally coupled, generating an ELD with alternated four‐ and eight‐membered carbon rings. Band structure, electronic density of states, wave functions, scanning tunneling microscope image, and quantum transport are analyzed. Unlike the conventional semiconducting behavior of AGNRs, the authors demonstrated that AGNRs with a 4‐8‐ELD exhibit a metallic behavior for n = m = 3p + 2 (p ≥ 0). They further demonstrate that graphene with 4‐8‐ELDs is metallic compared to the semi‐metallic behavior shown by the pristine graphene. Additionally, they investigate the effect of a single vacancy placed at the 4‐8‐ELDs on the electronic properties of AGNRs. The present investigation provides a theoretical basis to tailor graphene structures with possible applications in electronic devices. [ABSTRACT FROM AUTHOR]

Nitrogen-doped multiwalled carbon nanotube (CNT) bundles exhibiting pine-tree-like morphologies were synthesized on silicon–silicon oxide (Si/SiO2) substrates using a pressure-controlled chemical vapor deposition process. Electron field emission (FE) measurements showed a notable emission improvement at low turn-on voltages for the CNT pine-like morphologies (e.g., 0.59 V/µm) in comparison with standard aligned N-doped CNTs (>1.5 V/µm). We envisage that these pine-tree-like structures could be potentially useful in the fabrication of efficient FE and photonic devices. [ABSTRACT FROM PUBLISHER]