Lammot du Pont (1831-1884) was the son of Alfred Victor du Pont (1798-1856) and Margaretta Lammot du Pont (1807-1898). He graduated from the University of Pennsylvnia in 1849 and began working for E.I. du Pont de Nemours & Co. in 1850, becoming one of the premier chemists of the firm. He received several patents; the most notable was for the introduction of sodium nitrate in the manufacture of powder, which revolutionized the industry. During the Civil War, he worked with the United States government to purchase supplies of saltpeter abroad. Lammot du Pont eventually left the company and organized the Repauno Chemical Co. to manufacture high explosives. He was killed in an explosion of nitrogycerin at the company plant in 1884.

Lammot du Pont married Mary Belin (1839-1913) in 1865; ten of their eleven children survived to adulthood.