Comparative study on the gas-sensing performance of ZnO/SnO2 external and ZnO–SnO2 internal heterojunctions for ppb H2S and NO2 gases detection

Phan Hong Phuoc, Nguyễn Ngọc Việt, Viet Thong Le, Chu Manh Hung, Nguyễn Đức Hòa, Nguyễn Văn Duy, Hoang Si Hong, Nguyễn Văn Hiếu