Ultrasensitive Fiber-Based ZnO Nanowire Network Ultraviolet Photodetector Enabled by the Synergism between Interface and Surface Gating Effects

Abstract

A flexible UV photodetector with a high on/off ratio is extremely important for environmental sensing, optical communication, and flexible optoelectronic devices. In this work, a flexible fiber-based UV photodetector with an ultrahigh on/off ratio is developed by utilizing the synergism between interface and surface gating effects on a ZnO nanowire network structure. The synergism between two gating effects is realized by the interplay between surface band bending and the Fermi level through the nanowire network structure, which is proved through the control experiments between the ZnO micro/nanowire photodetector and micro/nanowire junction photodetector, and the corresponding Kelvin probe force microscopy (KPFM) measurements. The on/off ratio of the fiber-based ZnO nanowire network UV photodetector reaches 1.98 × 10 8 when illuminated by 1.0 mW cm −2 UV light, which is 20 times larger than the largest reported result under the same UV illumination. This new UV sensor also has a high resolution to UV light intensity change in the nW cm −2 range. Furthermore, when the fiberbased photodetector is curved, it still shows excellent performance as above. This work gives a new effective route for the development of a high-performance UV photodetector or other optoelectronic detection devices.

Highly sensitive strain sensors based on piezotronic tunneling junction

“…Synthesis of ZnO nano/microwires. ZnO nano/microwires used in the experiment were synthesized using a chemical vapor deposition (CVD) method through a vapor-solid process 44 . First, 2.0 g of ZnO powder and 0.4 g of graphite powder were ground in an agate mortar to obtain a uniform mixture.…”

Self-Assembled Al Nanostructure/ZnO Quantum Dot Heterostructures for High Responsivity and Fast UV Photodetector

“…3c, d and S3. Compared with the pristine ZnO device, the τ rise and τ decay of the device Al/ZnO-300 decreased to ~ 0.79 s and ~ 0.24 s. The response speed of the Al/ZnO heterostructure photodetector was apparently superior to previously reported ZnO-based UV photodetectors [4,[30][31][32], and was even faster than our previously reported Cu/ZnO hybrid architecture photodetectors [1]. The light intensity dependence on the I ph was compared for the Al/ZnO heterostructure photodetector at an identical bias of 10 V as shown in Fig.…”

Using Novel Semiconductor Features to Construct Advanced ZnO Nanowires-Based Ultraviolet Photodetectors: A Brief Review

“…Meng et al reported a fiber-based ZnO NW network UV photodetector. The interface and surface gating effects were considered to investigate the optoelectronic performance of the photodetector [19]. Due to the one-dimensional size effect, ZnO NW would be completely depleted, which resulted in a large distance between the Fermi level and conduction band and a dramatic decrease of carrier density by several orders of magnitude in dark.…”

“…The current-voltage results showed that the photocurrent of the as-fabricated UV photodetector based on ZnO/Cu x O core-shell NW structure had a significant increase because of the type-II band alignment. Under UV illumination with a wavelength of 365 nm and at a bias of 1 V, the rise time and the recovery time were 43 s, and the responsivity, the external quantum efficiency and the detectivity were 43.95 A/W, 149.3% and 75.51×10 19 Jones, respectively. The results indicate that a type-II band alignment is formed at the heterointerface of ZnO/Cu x O.…”