Convert column of time (as character decimals from Excel) to time in R

Question

I'm trying to convert a column of time (which I imported from Excel) that R has converted into a decimal/character string back into hh:mm:ss time. I have seen many good answers (using library chron, for example), but I keep getting these errors:

 My data:
 > head(env$Time, 10)
     [1] "0.41736111111111113" "0.6020833333333333"  "0.45"                "0.47222222222222227" "0.5131944444444444" 
     [6] "0.51250000000000007" "0.47361111111111115" "0.44791666666666669" "0.35138888888888892" "0.45277777777777778"

    times(env$Time)
        Error in convert.times(times., fmt) : format h:m:s may be incorrect
        In addition: Warning message:
        In unpaste(times, sep = fmt$sep, fnames = fmt$periods, nfields = 3) :
          8173 entries set to NA due to wrong number of fields
        
    chron(times(env$Time))
        Error in convert.times(times., fmt) : format h:m:s may be incorrect
        In addition: Warning message:
        In unpaste(times, sep = fmt$sep, fnames = fmt$periods, nfields = 3) :
          8173 entries set to NA due to wrong number of fields
        
    strptime(env$Time, format = "%H:%M:%S")
        [1] NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA
        [38] NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA