Yes, if the motorhome weighs 3.5 tons or less, a sticker or e-vignette is required.
If the motorhome exceeds 3.5 tons, a heavy vehicle charge (LSVA) must be paid instead of a vignette.
Related articles:
What vehicles need a Swiss motorway vignette?
Where can I buy the Swiss motorway vignette?
What is the Swiss PSVA / LSVA?