PYROLYSIS PATHWAYS AND KINETICS OF THERMAL-DECOMPOSITION OF DIETHYLZINC AND DIETHYLTELLURIUM STUDIED BY MASS-SPECTROMETRY

The thermal decomposition of diethylzinc (Et2Zn) and diethyltellurium (Et2Te) has been studied both separately and combined using an isothermal reactor attached to a quadrupole mass spectrometer (QMS). Under helium and hydrogen atmospheres the decomposition of Et2Zn leads to ethene, ethane and n-butane; with D2 as a carrier gas C2H5D is produced. Pyrolysis of Et2Te leads to ethane and ethene only. With helium as the carrier gas, the activation energy for the pyrolysis was E almost-equal-to 52 kcal mol-1 for Et2Zn and E almost-equal-to 50 kcal mol-1 for Et2Te, first-order kinetics being assumed. Under a hydrogen atmosphere, the determination of the activation energy for the pyrolysis of Et2Zn was inaccurate with a first-order reaction rate, and the activation energy for the pyrolysis of Et2Te was reduced to E almost-equal-to 47 kcal mol-1. In the co-pyrolysis, which is close to the conditions of ZnTe growth, the principal trends are enhancement of Et2Te decomposition and an increase of the thermal stability of Et2Zn.