Visible light detectors based on individual ZrSe3 and HfSe3 nanobelts

Zinc triselenide (ZrSe3) and hafnium triselenide (HfSe3) nanobelts were synthesized using a chemical vapor transport method. Photodetectors based on individual nanobelts of ZrSe3 and HfSe3 were fabricated on SiO2/Si substrates, respectively, and the optoelectronic properties of both were evaluated. The ZrSe3 nanobelt photodetector showed a good photoresponse to wavelengths ranging from 405 nm to 780 nm. Under illumination with 650 nm light, the ratio of photoswitch currents reached 1.97 with a light on/off period of 50 s at a bias voltage of 5 V. The HfSe3 nanobelt photodetector also showed good photoresponse to wavelengths ranging from 405 nm to 650 nm, and the ratio of photoswitch currents, under illumination with 532 nm light, reached 2.2 with a light on/off period of 50 s at a bias voltage of 5 V. The photoresponse time of both the photodetectors was less than 0.4 s. The results demonstrated that ZrSe3 and HfSe3 nanobelts possessed excellent photoconductivity, and suggested that these photodetectors would have potential applications under a range of visible light conditions.