As an organic biogeochemist, Dr. Liu is mainly interested in understanding the source, distribution and diagenesis of natural organic matter in the ocean. The cycling and preservation of natural organic matter are important processes of global carbon cycling, thus elucidating these processes help better understand our current and future climate. Dr. Liu's research also includes understanding the source and fate of contaminants in the environment, such as petroleum hydrocarbons leaked due to oil spills and microplastics discharged to the ocean. Dr. Liu's research involves many analytical tools such as gas or liquid chromatography, mass spectrometry, pyrolysis, and infrared spectroscopy.