Here's how to do that, and maintain the same File Explorer icon:
1. On your desktop, right-click the mouse and choose New, Shortcut.
2. Type explorer.exe "path" (place the path to the folder you want to default), then click Next.
3. Name the shortcut, then click Finish.
4. Hold down Ctrl and drag the icon to your taskbar.
If you prefer a different icon, either just type the path name for step 2 above, and proceed. Or after Step 3, Right-click on the new icon, and choose a different icon.
This way, you can have several in the Taskbar, if that is what you want, each with an icon that illustrates something about that folder.
Please let me know if this answer solved your query...