RPG Student List


Khak Ho LIM

Doctor Candidate in Chemical and Biomolecular Engineering

Supervisor: Prof. Ka Ming NG


Research Topic

Synthesis and Characterization of Novel Thermoelectric Materials


Thermoelectric (TE) materials have drawn researchers’ attention in recent decades for use as an alternative green energy source, due to the limited natural resources and rising demands for reduction of CO2 emission. Current TE materials usually involve expensive and toxic inorganic heavy metals, thus high material and processing costs, yet less than satisfactory performance. A hybrid of electrical conducting polymer-polycarbazole (PCbz) and inorganic nanomaterials (NMs) is of high interest due to the synergistical coupling of the individual properties of PCbz and NMs. This thesis is, therefore, aimed to synthesize a TE material based on this hybrid structure that has a high figure of merit (ZT). The effects of molecular orientation and morphology of PCbz and its derivatives intrinsically, has been investigated in Chapter 1. Thin films and fibres of PCbz have been fabricated and the morphological effect is currently being investigated. An in-house setup has been built for the TE characteristic studies.
Four phases of sulphur- containing chalcogenides will be studied in Chapter 2. Synergistic effect of the polymer hybrid with four phases of sulphur-containing chalcogenides on TE properties will also be investigated in this chapter. Hybrid material of PCb and four phases of sulphur- containing chalcogenides was found to have electrical conductivity. The morphology effect of hybrid material will be further investigated.
Further studies of TE characteristics on substituted carbazole (Cbz) and PCbz will be conducted on Chapter 3. These derivatives of Cbz and PCbz will again form hybrids with four phases of sulphur-containing chalcogenides and the TE characteristics will then be investigated.
In Chapter 4, a new family of Na(Co1-yCuy)2O4 will be synthesized and then form hybrids with PCbz and its derivatives. Similarly, the heterostucture and morphology effect on TE properties of these polymer-metal oxide hybrids will be investigated.