I'll arrived at chengdu airport at 23:00, planning to take a bus to jiuzhaigou at the next morning.

According to your situation, you are suggested to find a hotel nearby Xinnanmen Bus Station and take a direct long-distance bus to Jiuzhaigou in the next early morning.
As I know, there are several nice and budget hotels nearby that bus station. Home Inn (Xinnanmen Branch) is recommended. The price is CNY 150-200 per night. It's located at No.8, Nantai Road, Wuhou District.
From the airport, you can take airport shuttle bus line 1 to get to Provincial Gymnasium first. Then take a taxi to your hotel directly. The cab fare is about CNY 10 at night.