| Ga2O3,with a band gap of 4.9 eV,is a new type of ultra wide band gap semiconductor.Due to its special and excellent optical,electrical,gas-sensitive,and catalytic properties,Ga2O3 has shown great potential in solar-blind photodetectors,ultra-high voltage power devices,light-emitting diodes,gas sensors,solar cells and photocatalysis.It is the current research hotspot and frontier in the field of materials science.With the rapid development of intelligent wearable electronic devices,flexible electronics has become a hot field of scientific research and industrial application.Ga2O3-based flexible solar-blind photodetectors have broad application prospects in wearable optoelectronic devices,portable ultraviolet light monitoring,medical sensor monitoring,and intelligent robots.However,currently reported Ga2O3-based flexible solar-blind photodetectors are mostly obtained by depositing Ga2O3 amorphous films on polymers at low temperature,and the devices usually show instability.In addition,flexible devices are limited to maximum operating temperatures since polymers generally have low glass transition temperatures.Aiming at the hot and difficult problems in the research of Ga2O3-based flexible solar blind photodetectors and the catalytic properties of Ga2O3 nanomaterials,some research work has been carried out on the in-situ preparation of Ga2O3 nanomaterials and the application of Ga2O3-based flexible solar-blind photodetectors,as well as the photocatalysis and electrocatalysis applications of Ga2O3 nanorod arrays(NRAs).The main contents and results are as follows:1.High crystallinity ?-Ga2O3 nanowires were in-situ prepared at high-temperature on glass fiber fabrics by chemical vapor deposition(CVD)method.The effects of growth atmosphere,growth time,and growth temperature on the morphology of ?-Ga2O3 nanowires were investigated.The results showed that the morphology of ?-Ga2O3 nanowires is uniform when the growth temperature is 850? and the growth time is 5 h.Moreover,the morphology of ?-Ga2O3 nano wires is obviously different under the conditions that the mixed gas flow ratios of N2 and O2 are 1:1 and 10:1.XPS analysis confirmed that there were more oxygen vacancy defects in the ?-Ga2O3 nanowires prepared in a low oxygen atmosphere2.Two kinds of ?-Ga2O3 nano wires were fabricated into flexible photoconductive and flexible photovoltaic solar-blind photodetectors,and their photoelectric properties were studied.As a result,the flexible photoconductive solar-blind photodetector exhibits the obvious solar-blind photoelectric properties.The device exhibits a light-dark current ratio of 223.9,a responsivity of 0.9 A/W,a response time of only 0.17 s under 254 nm light with the light intensity of 1.2 mW/cm2,and the performance is not affected by bending conditions.The flexible photovoltaic solar-blind photodetector exhibits excellent Schottky rectifying characteristic and self-powered characteristic.The device has a photocurrent of 101.4 pA,a light-dark current ratio of 507,and a response time of 0.41 s under the light intensity of 1.2 mW/cm2 at 254 nm of 0 V bias.The band structure analysis indicates that the Schottky barrier is formed between the electrode and ?-Ga2O3 nanowires.3.Large-area Ga2O3 NRAs with controllable ?/? phase junction were in-situ prepared on glass fiber fabrics by hydrothermal method.The results show that the ?/?-Ga2O3 phase junction NRAs can be formed by annealing ?-Ga2O3 NRAs at 700? for 20-90 min,and the morphology of the Ga2O3 NRAs does not change significantly during annealing.For the photocatalytic performance test of the Ga2O3 NRAs,the results show that the ?/?-Ga2O3 phase junction NRAs(annealing the ?-Ga2O3 NRAs at 700?.for 60 min)shows significant photocatalytic degradation performance.The degradation rate can reach 97%under 60 min ultraviolet light.The enhancement mechanism of photocatalysis was closely related to the formation of the second type of band structure.In addition,the electrocatalytic performance of Ga2O3 NRAs was also investigated. |
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