Professor Liu’s research has centred on petroleum and natural gas geology and geochemistry, with particular emphasis on natural gas geological theory, the genetic mechanisms and evolutionary processes of hydrocarbons, noble gas isotope geochemistry, natural gas geochemical tracing systems, polygenetic hydrocarbon generation in China’s marine strata, and the accumulation mechanisms and distribution patterns of high-sulphur natural gas. He has led more than fifty national and major enterprise research projects, including National Science and Technology Tackling Key Problems projects, National Natural Science Foundation of China projects, major Chinese Academy of Sciences fund projects, and major Sinopec research projects. Author of more than ten monographs and over 300 peer-reviewed publications, his work has contributed to the development of petroleum and natural gas geochemistry and to research on hydrocarbon formation, accumulation, and resource exploration. Through sustained research and project leadership, Professor Liu has connected fundamental advances in petroleum geochemistry with practical applications in hydrocarbon exploration, resource assessment, and energy security.