ZnO-Paper Based Photoconductive UV Sensor

We build sensors, capable of detecting and measuring ultraviolet (UV) light, by depositing zinc oxide (ZnO) powder from a solvent suspension over common white paper. Although these sensors are easy to fabricate and require inexpensive materials, they feature characteristics similar to those of UV sensors made with complex and expensive procedures. The good performance in terms of conductivity change of our simple devices can be attributed to the conductivity and porosity properties of paper, which effectively binds the ZnO crystals. We perform analyses using quantum chemistry methods to describe possible mechanisms that explain the conductivity changes observed on the ZnO surface due to doping interactions with interstitial hydrogen and doping depletion caused by oxygen adsorption.