Enhancing the sensitivity and selectivity of pyrene-based sensors for detection of small gaseous molecules via destructive quantum interference

Abstract

Graphene-based sensors are exceptionally sensitive with high carrier mobility and low intrinsic noise, and have been intensively investigated in the past decade. The detection of individual gas molecules has been reported, albeit the underlying sensing mechanism is not yet well understood. We focus on the adsorption of NO${}_2$, H${}_2$O, and NH${}_3$ on a molecular junction with a pyrene core, which can be considered as a minimal graphene-like unit. We systematically investigate the chemiresistive response within the framework of density functional theory and non-equilibrium Green's functions. We highlight the fundamental role of quantum interference (QI) in the sensing process, and we propose it as a paradigmatic mechanism for sensing. Owing to the open-shell character of NO${}_2$, its interaction with pyrene gives rise to a Fano resonance thereby triggering the strongest chemiresistive response, while the weaker interactions with H${}_2$O and NH${}_3$ result in lower sensitivity. We demonstrate that by exploiting destructive QI arising in the meta-substituted pyrene, it is possible to calibrate the sensor to enhance both its sensitivity and chemical selectivity by almost two orders of magnitude so that individual molecules can be detected and distinguished. These results provide a fundamental strategy to design high-performance chemical sensors with graphene functional blocks.

9 pages, 7 figures

References in corpus (10)

• Detection of Individual Gas Molecules Absorbed on Graphene
• Adsorption of H2O, NH3, CO, NO2, and NO on graphene: A first-principles study
• Fermi level alignment in molecular nanojunctions and its relation to charge transfer
• Quantum Interference in Graphene Nanoconstrictions
• Charge Transport and Conductance Switching of Redox-active Azulene Derivatives
• Destructive quantum interference in electron transport: A reconciliation of the molecular orbital and the atomic orbital perspective
• Quantum interference assisted spin filtering in graphene nanoflakes
• Quantum interference in coherent tunnelling through branched molecular junctions containing ferrocene centers
• Electrode effects on the observability of destructive quantum interference in single-molecule junctions
• Robust conductance zeroes in graphene quantum dots and other bipartite systems

Cited by in corpus (2)

• Stability of destructive interference antiresonances in electron transport through graphene nanostructures
• A General Algorithm For Determining The Conductivity Zeros In Large Molecular Nanostructures: Applications To Rectangular Graphene Sheets