Hurst returned to Cambridge after the war to complete his PhD in physical chemistry.  In 1948 he joined the Atomic Energy Research Establishment at Harwell, working first on the chemistry of plutonium, before heading a team that investigated the potential of different types of nuclear reactors. In 1957, he was appointed chief chemist at the Atomic Energy Authority Industrial Research and Development branch at Risley, Cheshire, and in 1958 he was named as the first director of the Dounreay experimental fast-breeder reactor complex.
In 1963, Hurst left Dounreay to take up the directorship of the British Ship Research Association.
In the 1973 Queen's Birthday Honours, Hurst was appointed a Commander of the Order of the British Empire.