For workflow being able to create folders, you need to assign the folder content type to the list and then create new item from workflow using folder content type.
Add folder content type in list
- Open the list in an internet browser. There will be an option bar at the top.
- Select “List” and choose “List Settings” in the new ribbon.
- Click on “Advanced Settings”, activate the option “Enable management of content types” and click on “OK”.
- Back to the list settings.
- Click on “Add from existing content types”.
- In the new page, select “Folder Content Type” from the dropdown menu.
- Add the content type named “Folder” to the list content types by selecting it and clicking on the arrow pointing to the right.
- Click on “OK” to save the new assignment.
Now folder content type is added in list. Now create workflow on list which will create folder in list
Create folder using workflow
- To create a folder, choose the action “Create a list item”.
- Click on action to fill more information.
- Choose the list where the folder shall be added from the dropdown field.
- If your list has multiple content types, a field to assign a value to, will automatically be added. It is called “Content Type ID”. If it is not present, click on “Add” to add this field.
- Select “folder” from dropdown.
- Set title field for folder name.
Now your folder will be create through workflow. Folder can also create in document library through workflow by same procedure.