P12: 2d-materials-based sensing in liquid solvents

Supervision:Lucio Colombi Ciacchi, Gabriele Penazzi

Motivation and state of the art: Graphene and related materials have promising potential applications as active sensor elements for the detection of toxic ions, drugs or DNA oligomers. Their sensing ability is based on detectable changes either of their intrinsic transport properties upon interaction with analytes or of their selective adsorption affinity, measured for instance by force spectroscopy techniques. In order to investigate how the interactions with different supports and solvents (polar, non-polar, ionic etc.) affect the transport and adhesion properties, a novel combination of classical force fields with quantum transport schemes for various 2d material/liquid interfaces will be developed.

Own work: We have performed atomistic studies of solvated materials at different description levels, in particular predicting the adsorption configurations and free energy profiles of both simple molecules (water, amino acids, DNA basis) and more complex systems (polypeptides, oligonucleotides) at liquid/solid interfaces. We have developed and applied methods for the study of electron transport in low-dimensional materials in realistic environments.

Aims and work plan:We will develop and optimize accurate interaction potentials for 2d materials/liquid interfaces and study the polarization patterns, the shift of phonon frequencies and the change of the interfacial structures induced by molecular adsorption on graphene, graphene oxide and TMDC sheets in different liquid environments (water, ethanol, benzene etc.). Analyte molecules will include mercury ions, cocaine, nucleotides and peptides. Information gained with classical MD methods, which will also exploit the intra-molecular potentials developed in P1, will be interfaced with transport models developed in P11. The results will be used to establish sensing concepts for realistic devices.