This article presents a sensitive and selective sensor based on an individual zinc oxide nanotetrapod and on crossed ZnO nanorod for detection of UV light and hydrogen at low temperature. It is demonstrated that ZnO tetrapod has potential application as UV and as chemical sensor with multi-terminal construction. The chemisorbed gas molecules on a surface can extract or donate electrons to nano-material and this effect was used for monitoring the electrical resistance values change of the tetrapod sensor. We demonstrate that the ZnO tetrapod sensor demonstrate sensitivity and selectivity in resistance upon exposure to UV light, H2, O2, NH3 and LPG gas. The resistivity change is different for UV and for H2 gas sensing
