AppleScript: How to create a file that contains a forward slash in its filename?
You should never use the forward slash (/) in your filenames.

As an experiment, I opened TextEdit and saved a file with a forward slash in the name



Listing out the directory comments we get:

$ ls
total 8
drwxr-xr-x   3 areed  staff   102B May  9 02:02 .
drwx------+ 29 areed  staff   986B May  9 02:05 ..
-rw-r--r--@  1 areed  staff   325B May  9 02:00 Test:this.rtf


It changes the forward slash out to a colon.

An interesting thing happens when you use bash's autocomplete function; hit tab more than once and instead of "stopping" when it has found the full match, it keeps going:

$ cat Test\:this.rtf Test\:this.rtf Test\:this.rtf Test\:this.rtf Test\:this.rtf Test\:this.rtf


In the above example, I typed cat Tes and then pressed Tab 5 times.  Instead of beeping and stopping, it kept repeating as if stuck in a loop; this is not correct behavior.

Doing a search on this behavior, I stumbled across this article from C|Net:  Do not use "forward slash" in Mac OS X filenames, Distiller 6.0 example.  The article is quoted as saying:


  The forward slash should also never be used in the name of a drive or
  partition, or virtually in any other name field in Mac OS X. The
  reason behind this limitation stems from Mac OS X's UNIX underpinnings
  
  In prior versions of Mac OS the location of a file was noted using a
  path, with the colon ( :) separating objects. Mac OS X uses the
  forward slash ( /) in place of the colon.


It seems that this behavior/limitation is still present in macOS.  Bottom line, don't use the forward slash in your filename.