Nitrogen, one of the most chemically inactive molecules, does not adsorb on A1
2O
3 and Pt/Al
2O
3 catalysts at room temperature. However, once it was excited by plasma discharge using radio-frequency (13.56 MHZ), activated adsorption of nitrogen occurred on Pt/Al
2O
3 and Al
2O
3 at room temperature. The characterization of chemisorbed N
2 and its chemical reactivity with hydrogen have been studied by temperature programmed desorption (TPD) and infrared spectroscopy (IR). The adsorbed nitrogen on Pt/Al
2O
3 or Al
2O
3 was desorbed below 300°C by TPD, and IR spectra of the adsorbed nitrogen on Pt/Al
2O
3 were observed at ca . 2260 and 2230 cm
-1, which were assigned to N-N stretching vibration. Since almost the same absorption bands were observed with N
2 on Al
2O
3, it was considered that N
2(a) was chemisorbed mainly on the Al
2O
3 support . The H
2 exposure experiment at room temperature showed that the infrared bands of N
2(a) on the Al
2O
3 support (without Pt) did not change, but the intensity of the spectrum of N
2 on the Pt/Al
2O
3 catalyst decreased significantly with time. Moreover, NH
3 was detected in the liquid N
2 trap by GC after the TPD run. It was proposed that the N
2(a) reacted with the hydrogen spilt-over from the Pt surface to form other species like NH
x(a) (X=1∼3) even at room temperature.
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