Is there any bus from Chongqing to Jiuzhaigou? Which bus station and what number?

Yes, there are only two direct long-distance bus. One from Main Bus Station is scheduled at 08:00. The ticket fare is CNY 216 per person. The other one from the South Square Bus Station of the North Railway Station. It costs CNY 218 per person.
About the return way, there is only one bus from Jiuzhaigou Bus Station. The departure time is 07:30. :)