A Cr2O3-doped graphene sensor for early diagnosis of liver cirrhosis: a first-principles study.

Liver cirrhosis is among the leading causes of death worldwide. Because of its asymptomatic evolution, timely diagnosis of liver cirrhosis via non-invasive techniques is currently under investigation. Among the diagnostic methods employing volatile organic compounds directly detectable from breath, sensing of limonene (C10H16) represents one of the most promising strategies for diagnosing alcohol liver diseases, including cirrhosis. In the present work, by means of state-of-the-art Density Functional Theory calculations including the U correction, we present an investigation on the sensing capabilities of a chromium-oxide-doped graphene (i.e., Cr2O3-graphene) structure toward limonene detection. In contrast with other structures such as g-triazobenzol (g-C6N6) monolayers and germanane, which revealed their usefulness in detecting limonene via physisorption, the proposed Cr2O3-graphene heterostructure is capable of undergoing chemisorption upon molecular approaching of limonene over its surface. In fact, a high adsorption energy is recorded (∼-1.6 eV). Besides, a positive Moss-Burstein effect is observed upon adsorption of limomene on the Cr2O3-graphene heterostructure, resulting in a net increase of the bandgap (∼50%), along with a sizeable shift of the Fermi level toward the conduction band. These findings pave the way toward the experimental validation of such predictions and the employment of Cr2O3-graphene heterostructures as sensors of key liver cirrhosis biomarkers.

Performance Enhancement of Solar Cell by Incorporating Bilayer RGO-ITO Smart Conducting Antireflection Coating.

Multilayered graphene deposited on a flat resistive surface has twofold benefits. Less electronic scattering reduces the sheet resistance of the combined bilayer and high photon scattering through the unavoidable wrinkles on the chemically synthesized graphene layer leads to decreased effective reflection. In this paper, wet-chemically-synthesized reduced graphene oxide (RGO) has been employed on the top of the indium-doped tin-oxide (ITO) layer. The ITO layer of optimized thickness has been deposited as an alternative antireflection coating (ARC) on a p/n junction based crystalline silicon solar cell with standard textured surface. Variation in spectral response has been studied experimentally for different thickness and surface coverage of RGO on ITO. The combined effect of reduced sheet resistance due to high surface conductivity and increased photon injection efficiency due to scattering from the wrinkles of RGO results in significant improvement in the performance of the solar cell. By employing optimum thickness of RGO, percentage enhancements of about 18% and 10%, respectively, in efficiency and short-circuit current density have been achieved over the baseline cell structure. RGO also exhibits an additional benefit as a moisture repelling layer.

Outstanding Room-Temperature Hydrogen Gas Detection by Plasma-Assisted and Graphene-Functionalized Core-Shell Assembly of SnO2 Nanoburflower.

Here, we have reported the synthesis of three-dimensional, mesoporous, nano-SnO2 cores encapsulated in nonstoichiometric SnO2 shells grown by chemical as well as physical synthesis procedures such as plasma-enhanced chemical vapor deposition, followed by functionalization with reduced graphene oxide (rGO) on the surface. The main motif to fabricate such morphology, i.e., core-shell assembly of burflower-like SnO2 nanobid is to distinguish gases quantitatively at reduced operating temperatures. Electrochemical results reveal that rGO anchored on SnO2 surface offers excellent gas detection performances at room temperature. It exhibits outstanding H2 selectivity through a wide range, from ∼10 ppm to 1 vol %, with very little cross-sensitivity against other similar types of reducing gases. Good recovery as well as prompt responses also added flair in its quality due to the highly mesoporous architecture. Without using any expensive dopant/catalyst/filler or any special class of surfactants, these unique SnO2 mesoporous nanostructures have exhibited exceptional gas sensing performances at room temperature and are thus helpful to fabricate sensing devices in most cost-effective and eco-friendly manner.