Thermal Transport Of Fullerene And Its Derivatives

Thermal property is one of the most fundamental properties of matter. Taking vigorous action to research the mechanism and process of the material energy（heat） transport is helpful to the comprehensive understanding of the three major transport modes in nature. In low-dimensional systems, thermal transport is a dynamic research area. Owing to its unique structure and special physical properties, chemical properties, optical properties and biological properties, fullerene(C₆₀) has become an important material for micro / nano devices. As one of the most important branch in carbon nano materials, to study the thermal transport properties of C₆₀ and its derivatives is an integral part for the comprehensive understanding of carbon nano materials.We have investigated the thermal transport properties of C₆₀ and its derivatives by using the nonequilibrium molecular dynamics method. We have investigated the relationship of the thermal transport properties of fullerene with average temperature, the type and number of rare gas caged in C₆₀, the defect number and position in C₆₀. The thermal transport properties of one-dimensional crystal, superlattice and quasicrystal C₆₀ chains have also been studied. We explain the research results by analyzing the characteristics of the structure and phonon spectrum of fullerene. The specific research productions mainly include the following three parts:First of all, embedding a certain number of rare gases in C₆₀ molecule can make the thermal transport properties become worse. More rare gas atoms enclosed in C₆₀ means lower thermal conductivity of the C₆₀, and the bigger of the rare gas molecular radius means the more obvious suppressed of the thermal transport properties.Moreover, defects will significantly alter the thermal transport properties of C₆₀. Almost all of the single point defects cause the thermal conductivity of C₆₀ to get worse. However, double defects in C₆₀ have complicated influence on the thermal conductivity, which closely depends on the position of the defects.Eventually, due to its special structure, the superlattice / quasicrystal C₆₀ chain has a great influence on the thermal transport properties. From the simulation results of ideal harmonic oscillator, the thermal transport property of superlattice structure is smaller than that of the crystal structures. In the models of one dimensional C₆₀ chain, the similar result was found: the superlattice structure is disadvantageous to the thermal transport, and the quasicrystal structure has the maximum inhibition of the thermal transport.