Fabrication And Characterization Of SbSI Microrod Flexible Photodetectors

The ternary V-VI-VII compound antimony sulfur iodine?SbSI?is a special material that integrates various properties such as piezoelectricity,pyroelectricity,ferroelectricity,and photoelectricity.Its physical properties determine the broad application prospects in many fields.In this dissertation,the SbSI microrods with high flexibility are mainly explored by improving the hydrothermal method,and a flexible photodetector is researched for photoelectric performance.The details are as follows:1.The SbSI microrods were prepared by an improved hydrothermal methIn the reaction,sulfur powder was used instead of thiourea as the reaction sulfur source.It has been found that the synthesized product has good quality,with a length of 7 mm and band gap of about 1.87 eV.For the first time,a single SbSI microrod flexible photodetector is fabricated on a polyimide?PI?flexible substrate.The photoelectric test results show that the flexible device has excellent photoresponse in the wavelength range of 550-700 nm.Responsivity up to 17.5 mA/W at 5 V and635 nm wavelength,fast response speed?rise time and fall time are 73 ms and 146 ms respectively?,noise equivalent power of noise(2.91×10^-1313 W/Hz^1/2)and higher specific detectivity?5.43×10¹00 Jones?comparing with the previously reported SbSI photodetectors which is an order of magnitude higher than them.Meanwhile,the optical properties of this flexible device can rival with rigid device?SiO₂/Si substrate?.Especially,our hydrothermal synthesized SbSI microrods have wonderful flexibility,mechanical stability and folding resistance.The photoelectric properties and response characteristics are almost unchanged after different bending curvatures and 2000 bends.The results show that SbSI microrods have broad application prospects in the field of high performance,low cost optical detection and flexible devices.2.In the above study,it was found that Sb₂S₃ can be generated by changing the molar ratio of the raw materials of the SbSI reaction.The synthesized sample has a rod-like structure with a diameter of tens of microns and a length of up to 5 mm.The related characterization results certificated that the product has an orthorhombic structure.A single of Sb₂S₃microrod photodetector is fabricated on the substrate of SiO₂/Si and conducted the photoelectric testing.The results show that the device has a wide spectral response range and obvious light response in the wavelength range of 300-800 nm,especially in the wavelength range of 600-800 nm.The responsivity at 5 V bias voltage and 730 nm wavelength is 75 mA/W,and rise time and fall time are 110 ms and 810 ms,respectively,which is superior to the reported Sb₂S₃ nanoarray photodetectors.3.The CdSe nanobelt photodetectors with a line width of only 10?m were fabricated on SiO₂/Si substrates using photolithography.This device has exceptional stability;high on-off ratio?563?;rapid response time?less than 68 ms?;high specific detectivity?1.74×10¹22 Jones?;relatively high responsivity?1.39 A/W?.The above preliminary results provide the experimental basis for the successive fabrication of micro-nano SbSI structure rigid/flexible device.