Curie received another great honor in 1911, winning her second Nobel Prize, this time in chemistry. She was selected for her discovery of radium and polonium, and became the first scientist to win two Nobel Prizes. While she received the prize alone, she shared the honor jointly with her late husband in her acceptance lecture.
Around this time, Curie joined with other famous scientists, including Albert Einstein and Max Planck, to attend the first Solvay Congress in Physics. They gathered to discuss the many groundbreaking discoveries in their field. Curie experienced the downside of fame in 1911, when her relationship with her husband's former student, Paul Langevin, became public. Curie was derided in the press for breaking up Langevin's marriage. The press' negativity towards Curie stemmed at least in part from rising xenophobia in France.
When World War I broke out in 1914, Curie devoted her time and resources to helping the cause. She championed the use of portable X-ray machines in the field, and these medical vehicles earned the nickname "Little Curies." After the war, Curie used her celebrity to advance her research. She traveled to the United States twice— in 1921 and in 1929— to raise funds to buy radium and to establish a radium research institute in Warsaw.