# Wide Response Range Photoelectrochemical UV Detector Based on Anodized TiO2-Nanotubes@Ti@quartz Structure

## TL;DR

A new UV detector design using anodized TiO2 nanotubes extends the detection range to shorter wavelengths and improves stability.

## Contribution

A built-in electron collector design in the active material extends the UV response range and avoids electrode interference.

## Key findings

- The TiO2-nanotubes@Ti@quartz structure absorbs near-UV light from 240–400 nm.
- The device shows a response time below 100 ms and good switching characteristics.
- Optimal synthesis conditions were determined using electrochemical impedance analysis.

## Abstract

Conventional sandwich structure photoelectrochemical UV detectors cannot detect UV light below 300 nm due to UV filtering problems. In this work, we propose to place the electron collector inside the active material, thus avoiding the effect of electrodes on light absorption. We obtained a TiO2-nanotubes@Ti@quartz photoanode structure by precise treatment of a commercial Ti mesh by anodic oxidation. The structure can absorb any light in the near-UV band and has superior stability to other metal electrodes. The final encapsulated photoelectrochemical UV detectors exhibit good switching characteristics with a response time below 100 ms. The mechanism of the oxidation conditions on the photovoltaic performance of the device was investigated by the electrochemical impedance method, and we obtained the optimal synthesis conditions. Response tests under continuous spectroscopy confirm that the response range of the device is extended from 300–400 nm to 240–400 nm. This idea of a built-in collector is an effective way to extend the response range of a photoelectrochemical detector.