Pulsed‐Laser‐Deposition Fabricated ZnIn₂S₄ Photodetectors with Excellent ON/OFF Switching Characteristics toward High‐Temperature‐Resistant Photodetection Applications

Abstract

The extensively explored unary and binary 2D layered materials (2DLMs) based photodetectors suffer from deficiencies of either poor stability, or indistinctive photoswitching, or poor scalability, or low durability to high‐temperature environment. Herein, a two‐step scenario, pulsed laser deposition (PLD) followed by post‐deposition annealing, is developed to produce centimeter‐scale 2D ZnIn2S4 (ZIS) nanofilms. Transport characterizations indicate that the as‐fabricated ZIS photodetectors manifest outstanding photosensitivity with an on/off switching ratio beyond 1000 upon 405 nm illumination. Beyond this, it is revealed that the photoresponse of the ZIS photodetectors increases with increasing channel thickness, where a responsivity of 1.4 A W−1, an external quantum efficiency of 430% and a detectivity of 9.8 × 109 Jones (1 Jones = 1 cm Hz1/2 W–1) are demonstrated with a pulse number of 10 000. In addition, these devices without encapsulation maintain stable within 1900 photoswitching cycles and over a one‐month storage in air. Furthermore, robust photoswitching is demonstrated under an operating temperature up to 150 °C. In summary, all these findings establish that PLD provides a powerful route to produce large‐scale multielement 2DLMs and the PLD‐derived ZIS photodetectors hold grand prospect for photoelectric technologies in specific high‐temperature environments (e.g., the lunar exploration program).

High-performance hierarchical O-SnS/I-ZnIn2S4 photodetectors by leveraging the synergy of optical regulation and band tailoring

“…35,36 Prior to the assembly of the heterostructures, the optimized growth conditions for preparing ZIS and SnS nanofilms have been systematically explored. The characterization results for pristine ZIS can be found in our preceding study, 20 while the characterization results for pristine SnS are summarized in Fig. S1 and S2 (ESI †).…”

“…S16, ESI †), which is comparable to that of a pristine ZIS photodetector. 20 On the whole, the comprehensive performance metrics of the SnS/ZIS photodetectors are on par with those of the state-of-the-art 2DLM based photodetectors (Table S1, ESI †) as well as 2DLM based heterojunction photodetectors (Table S2, ESI †). Of note, this strategy of integration of 3D-structured light-trapping SnS nanosheet networks is well compatible with many of the previously reported improvement methods such as dielectric engineering, 40 ferroelectric polarization coupling, 41 potential fluctuation engineering, 7 and multiple-gate modulation.…”

“…Of note, such a response rate is comparable to that of the PLD-derived pristine ZIS photodetector (≈15.3 ms/14.4 ms). 20 This is advantageous as compared to the previously reported surface engineering techniques, 23,52,53 where the de-trapping of the captured photocarriers is rather sluggish and the response/response time of the corresponding devices is thus commonly long. Moreover, it is to be emphasized that the response rate of the PLD-derived ZIS photodetectors is still much slower than that of the devices built of exfoliated ZIS single crystals in the current stage, 54,55 which indicates that the speed of the SnS/ZIS devices can probably be further accelerated by improving the crystallinity of the PLD-derived ZIS nanofilms in the future.…”

“…This is probably due to the outstanding thermal stability of both ZIS and SnS. 20,37 The Raman spectra of the PLD-derived ZIS, SnS and SnS/ZIS nanofilms upon 514 nm laser excitation are summarized in Fig. 1f.…”

“…In recent years, several 2DLMs with layer number-independent direct bandgap nature in a substantially wide thickness range have emerged, such as black phosphorus, 19 ZnIn 2 S 4 (ZIS), 20 In 2 Se 3 , 21 ReS 2 , 22 etc. As a consequence, the low light absorption issue of 2DLM optoelectronic devices can be addressed to some extent with these active materials by increasing the channel thickness.…”