Optoelectronic Modulation of Silver Antimony Sulfide Thin Films for Photodetection

Abstract

Silver antimony sulfide, as a ternary chalcogenide, has attracted great attention in the field of optoelectronics in recent years. In particular, it has appealing properties, such as excellent stability, solution processability, and versatile composition tunability. Benefiting from the recent development of processing techniques, AgSbS2 has emerged as a promising candidate for next-generation, thin-film photovoltaics. On the contrary, AgSbS2-based photodetectors have been barely reported. In this work, we systematically investigated the composition engineering of silver antimony sulfide compounds with a precursor route. Their optoelectronic properties were fully characterized, and the composition was optimized for photodetection. High-performance phototransistors were first reported based on field-effect thin film transistors with interfacial modification. The obtained AgSbS2 phototransistors exhibited relatively high photosensitivity, low dark current and noise, superior device stability, and excellent detectivity covering the whole range from ultraviolet to near-infrared, highlighting the great potential for next-generation photodetection.

Charge-Carrier Dynamics of Solution-Processed Antimony- and Bismuth-Based Chalcogenide Thin Films

“…The introduction of Ag­(I) in Sb 2 S 3 precursors yielded a decreased E g (1.51 eV) and a larger Urbach Energy ( E u ) of 147 meV. It is worth noting that the bandgap and Urbach tails may vary slightly owing to the film processing and could also be dependent on the composition . Overall, the comparison between antimony- and bismuth-based chalcogenides reveals that the latter present enhanced absorption coefficients (α) and reduced bandgaps.…”

“…It is worth noting that the bandgap and Urbach tails may vary slightly owing to the film processing and could also be dependent on the composition. 7 Overall, the comparison between antimony-and bismuthbased chalcogenides reveals that the latter present enhanced absorption coefficients (α) and reduced bandgaps. The Bi 2 S 3 thin films possess a bandgap of 1.46 eV and E u of 113 meV, and the AgBiS 2 films have the smallest bandgap of 1.15 eV with a E u of 116 meV.…”

“…Huang and coauthors introduced Sb 2 S 3 thin films for photodetection with a field-effect transistor structure . Jiang et al and Yang et al also reported phototransistors based on AgBiS 2 and AgSbS 2 , respectively, and achieved a tunable photogating effect. , …”

“…22 reported phototransistors based on AgBiS 2 and AgSbS 2 , respectively, and achieved a tunable photogating effect. 7,23 Despite these recent achievements, the device-centric development of chalcogenide semiconductors observed in the past years has been based mostly on trial−error approaches in device and materials engineering. Therefore, new crucial insights into charge-carrier generation, recombination and transport processes are urgently needed to reveal structure− function relations and provide essential feedback for device optimization.…”

“…Antimony- and bismuth-based chalcogenide semiconductors have attracted tremendous attention in the field of optoelectronics, benefiting from the facile and low-cost processing, superior stability, and ultrahigh and tunable absorption coefficients. In recent years, they have demonstrated great potential for multiple applications, ranging from next-generation thin-film photovoltaics, − photodetectors, , and phototransistors, , to photocatalysis. , In particular, solution-processed Sb 2 S 3 and AgBiS 2 -based solar cells have progressed rapidly. For example, Tang et al proposed a vacuum-assisted solution process for highly efficient Sb 2 S 3 solar cells and achieved a power conversion efficiency (PCE) of 6.78% .…”