Union Sekailwe joined him as the last placed qualifier, crossing the line in 24.01 seconds, behind Buis’ South African record time of 22.57.
"I’m very happy with my time and didn’t expect it because I slowed a bit towards the end," said Buis who hails from Riversdale in the Cape.
"I saw the other heat with Evan O’Hanlon (Australia) and he clocked a great time of 23.10 although he practically stopped before the end.
"So I’m very excited and know it will be a great race tomorrow -- we will push each other to our limits and the time will be spectacular."
Buis said it was good to have his team-mate Sekailwe in the final and they would give each other encouragement.
Another silver medallist who would be back on the track competing in Friday evening's semi-finals was Hilton Langenhoven, who qualified fourth fastest out of 20 athletes in the men’s T12 200m heats.
As some of the athletes in this visually impaired category run with guides, only four lanes would be used in each of the three semi-finals.
Langenhoven won his heat in 22.44 seconds while Poland’s Mateusz Michalski was fastest overall in 22.13.
Single-leg amputee from Potchefstroom, Casper Schutte, made his Paralympic debut in the men’s F42 javelin competition.
His best throw of 48.12 metres was a South African record but left him just outside the medal positions. China’s Yanlong Fu took the gold with a world record heave of 52.79m.