Chemical and Physical Properties of Nanostructures on Surface Investigated by Scanning Probe Microscopy

Ing. Vijai Meena SANTHINI, M.Sc.

Doctoral thesis

Abstract:

This thesis provides an alternative approach to traditional polymerization technique for synthesising polymers with organic molecules. It focuses on the growth of 1D polymers particularly metal coordinated polymers and polymers with organometallic monomers, on metal surfaces. The properties of these nanostructures on surfaces are studied with the help of Scanning Probe Microscopy (SPM) techniques. The growth of 1D metal coordinated polymers by co-deposition of transition metals and quinone molecules onto metal surfaces under ultra-high vacuum is explored, and a difference in metal coordination has been observed depending on the choice of metal. The structural and electronic properties of these 1D coordination polymers are characterized by means of STM/nc-AFM with CO-functionalized tips and supported by DFT and other theoretical calculations. The synthesis of H-bonded wires with the same precursor molecule has been discussed to emphasize the difference on metal coordination. A distinct 1D polymer made up of organometallic ferrocene monomer units on Ag(111) surface has been synthesised and the properties have been characterized with STM/nc-AFM technique. The charge transport in the 1D nanowire has been analysed by carrying out lifting experiments with the STM tip and a transport model has been devised theoretically.

Abstract:

This thesis provides an alternative approach to traditional polymerization technique for synthesising polymers with organic molecules. It focuses on the growth of 1D polymers particularly metal coordinated polymers and polymers with organometallic monomers, on metal surfaces. The properties of these nanostructures on surfaces are studied with the help of Scanning Probe Microscopy (SPM) techniques. The growth of 1D metal coordinated polymers by co-deposition of transition metals and quinone molecules onto metal surfaces under ultra-high vacuum is explored, and a difference in metal coordination has been observed depending on the choice of metal. The structural and electronic properties of these 1D coordination polymers are characterized by means of STM/nc-AFM with CO-functionalized tips and supported by DFT and other theoretical calculations. The synthesis of H-bonded wires with the same precursor molecule has been discussed to emphasize the difference on metal coordination. A distinct 1D polymer made up of organometallic ferrocene monomer units on Ag(111) surface has been synthesised and the properties have been characterized with STM/nc-AFM technique. The charge transport in the 1D nanowire has been analysed by carrying out lifting experiments with the STM tip and a transport model has been devised theoretically.

Keywords

1D polymers, metal coooridanted, organometallic, SPM, AFM, quinone, ferrocene

Language used: English

Date on which the thesis was submitted / produced: 2. 6. 2021

Thesis defence

• Supervisor: doc. Ing. Pavel Jelínek, Ph.D.

Palacký University Olomouc

Faculty of Science

Doctoral programme / field:
Chemistry / Physical Chemistry