Fritz Haber

Fritz Haber was born in Breslau, Prussia (now Wroclaw, Poland), in 1868, and educated at the St. Elizabeth Classical School, where he took an early interest in chemistry. After studying at the University of Berlin, he transferred to the University of Heidelberg in 1886 and studied under the famed German chemist Robert Bunsen. Haber was ultimately appointed professor of physical chemistry and electrochemistry at the Karlshruhe Institute of Technology. When scientists warned that the world would not be able to produce enough food to feed its growing human population in the 20th century, he listened.

Scientists knew nitrogen was crucial to plant life; they also knew the earth’s supply of usable quantities was quite limited. But Haber discovered a way to convert the nitrogen gas in the earth’s atmosphere into a compound that could be used in fertilizer. His process was soon scaled up by BASF’s great chemist and engineer Carl Bosch and became known as the Haber-Bosch process, enabling mass production of agricultural fertilizers and leading to a massive increase in growth of crops for human consumption. According to Vaclav Smil, a global agricultural historian at the University of Manitoba in Winnipeg, the Haber–Bosch process of synthesizing and manufacturing ammonia from nitrogen and hydrogen (and later industrialized by Carl Bosch, Haber’s brother-in-law) was likely the most important technological innovation of the 20th century. It sustains the food base for the equivalent of half the world’s population today.

In 1898 Haber published his textbook on Electrochemistry, which was based on the lectures he gave at Karlsruhe. In the preface to his book, he expressed his intention to relate chemical research to industrial processes and in the same year he reported the results of his work on electrolytic oxidation and reduction, in which he showed that definite reduction products can result if the potential at the cathode is kept constant. In 1898 he explained the reduction of nitrobenzene in stages at the cathode and this became the model for other similar reduction processes.

In 1901, Haber married the brilliant chemist Clara Immerwahr, the first woman to receive a doctorate from Breslau University. Years before, she’d spurned a marriage proposal from him to focus on her studies and career.  She began collaborating with her husband on a textbook on the thermodynamics of gas, and tried to continue her own research, writing and speaking. As her husband’s reputation spread, she learned that her audiences assumed that he had written her lectures. Meanwhile, Haber’s career flourished, and around the start of World War I, the German Army requested his help in the development of replacing explosives in shells with poison gasses.

In 1911 he was invited to become director of the Institute for Physical Chemistry and Electrochemistry at the new Kaiser Wilhelm Gesellschaft in Berlin, where academic scientists, government, and industry cooperated to promote original research.

During the war Haber threw his energies and those of his institute into further support for the German side. He developed a new weapon—poison gas, the first example of which was chlorine gas—and supervised its initial deployment on the Western Front at Ypres, Belgium, in 1915.

His promotion of this frightening weapon precipitated the suicide of his wife, Clara Immerwahr Haber, who was herself a chemist, and many others condemned him for his wartime role. There was great consternation when he was awarded the Nobel Prize in Chemistry for 1918 for the synthesis of ammonia from its elements.

After World War I, Haber was remarkably successful in building up his institute, but in 1933 the anti-Jewish decrees of the Nazi regime made his position untenable. He retired a broken man, although at the time of his death he was on his way to investigate a possible senior research position in Rehovot in Palestine (now Israel).