We have studied the adsorption of gas molecules (CO, NO, NO2, O2, N2, CO2, and NH3) on graphene nanoribbons (GNRs) using first principles methods. The adsorption geometries, adsorption energies, charge transfer, and electronic band structures are obtained. We find that the electronic and transport properties of the GNR with armchair-shaped edges are sensitive to the adsorption of NH3 and the system exhibits n type semiconducting behavior after NH3 adsorption. Other gas molecules have little effect on modifying the conductance of GNRs. Quantum transport calculations further indicate that NH3 molecules can be detected out of these gas molecules by GNR based sensor.

Adsorption of gas molecules on graphene nanoribbons and its implication for nano-scale molecule sensor

This theoretical study focuses on the adsorption, reactivity, topological analysis, and sensing behavior of metal-doped (K, Na, and Mg) aluminum nitride (Al12N12) nanoclusters using the first-principle density functional theory (DFT). All quantum chemical reactivity, natural bond orbital (NBO), free energies (ΔG, ΔH), and sensor parameters were investigated using the ωB97XD functional with the 6-311++G(d,p) basis set. The trapping of carboplatin (cbp) onto the surfaces of doped Al12N12 was studied using four functionals PBE0-D3, M062X-D3, ωB97XD, and B3LYP-D3 at the 6-311++G(d,p) basis set. Overall, the substantial change in the energy gap of the surfaces after the adsorption process affects the work function, field emission, and the electrical conductivity of the doped clusters, hence making the studied surfaces a better sensor material for detecting carboplatin. Higher free energies of solvation were obtained in polar solvents compared to nonpolar solvents. Moreover, negative solvation energies and adsorption energies were obtained, which therefore shows that the engineered surfaces are highly efficient in trapping carboplatin. The relatively strong adsorption energies show that the mechanism of adsorption is by chemisorption, and K- and Na-doped metal clusters acted as better sensors for carboplatin. Also, the topological analysis in comparison to previous studies shows that the nanoclusters exhibited very high stability with regard to their relevant binding energies and hydrogen bond interactions.

Metal-Doped Al12N12X (X = Na, Mg, K) Nanoclusters as Nanosensors for Carboplatin: Insight from First-Principles Computation.

A Theoretical study of HCN adsorption and width effect on co-doped armchair Graphene Nanoribbon

DFT outcome for comparative analysis of Be12O12, Mg12O12 and Ca12O12 nanocages toward sensing of N2O, NO2, NO, H2S, SO2 and SO3 gases

Sensing of SO3, SO2, H2S, NO2 and N2O toxic gases through aza-macrocycle via DFT calculations

Hydrogen sulfide gas sensor using osmium doped graphene nanoribbon: An insights from DFT study

The adsorption of toxic gases Nitrogen Oxide (NO) and Nitrogen Dioxide (NO2) on armchair graphene nanoribbon substrate and its co-doped system has been investigated. Density Functional Theory (DFT) is used to explain the gas sensing performance of Boron (B) doped and Boron-Phosphorus (BP) co-doped armchair graphene nanoribbon (BCmPn-Gr; m,n = 0,1,2,3 and m + n = 3) for detection of these gases. The change in electronic and structural characteristics of armchair graphene nanoribbon (ArGNRs) before and after sensing of NO and NO2 gases is reported. Different configurations are used in our work such as Pristine, Boron doped and Boron-Phosphorus co-doped ArGNRs. Boron site is observed to be active site to study adsorption phenomenon due to accumulation of positive charge around it. Boron-Phosphorus based formation shows considerable enhancement of adsorption capabilities as compared to pristine structure alone. A significant increase in adsorption of NO and NO2 gases with increase in amount of Phosphorus atoms is observed. This work reveals that Boron Phosphorus co-doped system is considerably better than previously reported similar works. It can be utilized as effective gas sensing material.

Enhanced sensitivity of graphene nanoribbon gas sensor for detection of oxides of nitrogen using boron and phosphorus co-doped system: A first principles study

Adsorption chemistry of co-doped graphene nanoribbon and its derivatives towards carbon based gases for gas sensing applications: Quantum DFT investigation

In the present study, we explored the sensing behavior of pristine gCN and transition metal (Au, Ag, Pd and Pt) doped gCN monolayer for CO gas molecule using DFT calculations. Structural and electronic properties such as adsorption energy, band structure and density of states (DOS) have been investigated. An increase of 17.03%, 15.08%, 2.24% and 4.99% is observed for Au, Ag, Pd and Pt doped gCN as compared to pristine gCN towards CO gases. Moreover the band gap also decreases considerably after doping transition metals in it which futher reduces after introduction of CO gas. DOS value also increases. The study revealed that the sensing performance of gCN is enhanced by doping the pristine form with the transition metals (Au, Ag and Pt) and hence doped gCN can be a favorable material for CO gas sensing.

B. C. Choudhary

Papers

A Theoretical study of HCN adsorption and width effect on co-doped armchair Graphene Nanoribbon

Hydrogen sulfide gas sensor using osmium doped graphene nanoribbon: An insights from DFT study

Enhanced sensitivity of graphene nanoribbon gas sensor for detection of oxides of nitrogen using boron and phosphorus co-doped system: A first principles study

Adsorption chemistry of co-doped graphene nanoribbon and its derivatives towards carbon based gases for gas sensing applications: Quantum DFT investigation

DFT based study of transition metals (Au,Ag,Pd& Pt) doped graphitic carbon nitride (gCN) monolayer as a CO gas sensor