Datetime values can be formatted to show only the time component but the time component cannot be separated from a date. To show only the time component in 24-hour clock format, use upper case HH
t_final = datetime(t,'Format','HH:mm:ss')
% 6×1 datetime array
% 12:24:05
% 10:36:05
% 04:07:55
% 01:25:51
% 01:48:05
% 13:30:10
Another possibility is using durations instead of datetime.
t_final = duration(t);
% 6×1 duration array
% 12:24:05
% 10:36:05
% 04:07:55
% 01:25:51
% 01:48:05
% 13:30:10
Does that achieve your goal?
