Hydrazine synthesis by N2-hydrogenation on solid surface was examined with various solid materials. Nitrogen molecule excited by glow discharge and its interaction with hydrogen source material held on solid surface were concluded to be vital for the steadily synthesis at room temperature. Ammonia with a little amount of hydrazine was formed on solid surface from discharging H2/N2 mixture with rate of Otil order dependence on the total pressure. The rate increased and the fraction of hydrazine in product decreased, with rise of the mixing ratio of H2 to N2 from zero to ca. 3. Such a course of the reaction of H2/N2 mixture was nearly independent of the sort of solid material. With N2 gas alone, OH groups chemisorbed on the solid surface was selectively used for the formation of hydrazine, however, the reaction was limitted in the early stage of the discharge. The steady formation of hydrazine from N2 was performed by the interaction of plasma of CH4/Nz mixture with solid surface or that of N z plasma with solid surface covered with higher hydrocarbons. A little amount of CN compounds but not ammonia was formed in this case and the product should be trapped off immediately after the interaction to suppress the formation of ammonia and CN compounds and to obtain hydrazine with high selectivity. Ammonia was useless for hydrazine synthesis with glow discharge, as it was simply decomposed and preferentially forms CN compounds under glow discharge in the presence of hydrocarbon. Monosilane was also useless as a hydrogen source for hydrazine synthesis from N 2, because of its high facility of decomposition in plasma to give hydrogen gas. In conclusion, the effect of glow discharge for hydrazine formation is based on the formation of excited N2 molecule (presumably A3 j'u+), which collides with OH groups or hydrocarbon held on the solid surface and drives out excited H atoms, presumably proton and/or radical, and are quenched as hydrazine molecule by the wall effect of the solid. The steady formation of ammonia from plasma of H z/N2 mixture may be caused by the simple wall effect of solid surface. *) A memorial paper for the author's retirement. **) Research Institute for Catalysis, Hokkaido University, Sapporo, 060 Japan.
