Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China;
School of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China;
Tsinghua-Berkeley Shenzhen Institute Tsinghua University Shenzhen 518055 China;
Carbon nanotube; Heterojunction; Solar cell; Photodetector; Gas sensor;