Travel in Switzerland is very friendly with public transport. The absolute reference to find/check your best travel itinerary is www.sbb.ch (also available via app in Google and Apple Store).
It includes all transport options (bus, train, boat, tram). To reach Empa there are several options:
- 10-15 min walk from Dübendorf train station
- Busstop called: Dübendorf, Empa
- Tram stop called: Dübendorf, Giessen (tram line #12 which goes straight to the airport as well)
To get to Switzerland all airports are decent options (Zürich, Bern-Belp, Basel, Geneva), for short travel times, ZH-Airport is highly recommended.
Please find here the link to the Zürich Card.
In general, this ticket will make sense if you travel frequently, e.g. staying at IBIS airport hotel.
But even then: ticket cost for a 24 hour ticket: around 9 Euro – for the two zones 110 and 121 (Zurich airport and downtown Zurich).