Thermal decomposition of surfactant coatings on Co and Ni nanocrystals

The pathway for thermal decomposition of an oleic acid surfactant protecting Co and Ni nanocrystals is identified by probing the relevant molecular orbitals with x-ray absorption spectroscopy. The two steps observed previously in thermogravimetric measurements are identified with thermal desorption of entire molecules at ≈200 °C and dehydrogenation at ≈400 °C, which leaves a graphitic surface with alkane fragments underneath.