Carrier recombination suppression and transport enhancement enable high‐performance self‐powered broadband Sb₂Se₃ photodetectors

Abstract

Antimony selenide (Sb2Se3) is a promising candidate for photodetector applications boasting unique material benefits and remarkable optoelectronic properties. Achieving high‐performance self‐powered Sb2Se3 photodetector through a synergistic regulation of absorber layer and heterojunction interface demonstrates great potential and needs essential investigation. In this study, an effective two‐step thermodynamic/kinetic deposition technique containing sputtered and selenized Sb precursor is implemented to induce self‐assembled growth of Sb2Se3 light absorbing thin film with large crystal grains and desirable [hk1] orientation, presenting considerable thin‐film photodetector performance. Furthermore, aluminum (Al3+) cation dopant is introduced to modify the optoelectronic properties of CdS buffer layer, and further optimize the Sb2Se3/CdS (Al) heterojunction interface quality. Thanks to the suppressed carrier recombination and enhanced carrier transport kinetics, the champion Mo/Sb2Se3/CdS (Al)/ITO/Ag photodetector exhibits self‐powered and broadband characteristics, accompanied by simultaneously high responsivity of 0.9 A W−1 (at 11 nW cm−2), linear dynamic range of 120 dB, impressive ON/OFF switching ratio over 106 and signal‐to‐noise ratio of 109, record total noise determined realistic detectivity of 4.78 × 1012 Jones, and ultra‐fast response speed with rise/decay time of 24/75 ns, representing the top level for Sb2Se3‐based photodetectors. This intriguing work opens up an avenue for its self‐powered broadband photodetector applications.

Tellurium Doping Inducing Defect Passivation for Highly Effective Antimony Selenide Thin Film Solar Cell

“…Antimony selenide (Sb 2 Se 3 ) has become a promising light-harvesting material, thanks to the advantages of high earth abundance, low toxicity, superior photoelectric properties, and a high light absorption coefficient [ 1 , 2 , 3 , 4 , 5 ]. Sb 2 Se 3 as a binary compound has high stability and fixed stoichiometry.…”

Charge Separation Enhancement Enables Record Photocurrent Density in Cu2ZnSn(S,Se)4 Photocathodes for Efficient Solar Hydrogen Production

“…[ 46 ] According to a previous report, it is favorable for simultaneously suppressing carrier recombination at interface and enhancing the carrier transfer across the interface. [ 47 ] In addition, the split of quasi‐Fermi levels including the hole quasi‐Fermi level ( E qFp ) and the electron quasi‐Fermi level ( E qFn ) under illumination are also portrayed in Figure 5e; the ideal photovoltage ( V ph ) determines the maximum onset potential ( V on ). Afterward, to gain a deeper insight of the nature of this CZTSSe/CdS heterojunction interface and its effect on photoelectric device performance, the corresponding photovoltaic devices with similar device configuration (i.e., Mo/CZTSSe/CdS/ITO/Ag) were fabricated, and labeled as PV‐1, PV‐2, and PV‐3, respectively.…”

Improved Carrier Lifetimes of CdSe Thin Film via Te Doping for Photovoltaic Application

“…The prepared Cd­(Se,Te) thin films present excellent material properties in terms of their morphology and optical absorption. The defects and carrier lifetime also play significant roles in the performance of CdSe optoelectronic devices . Previous experiments have shown that the average carrier lifetime of the CdSe thin film is less than 200 ps, which is the most important factor greatly limiting the efficiency.…”

“…The defects and carrier lifetime also play significant roles in the performance of CdSe optoelectronic devices. 31 Previous experiments have shown that the average carrier lifetime of the CdSe thin film is less than 200 ps, which is the most important factor greatly limiting the efficiency. As the DFT calculation mentioned above, the Te element serves as a good passivation for the CdSe thin films that can reduce the hole capture coefficient and the recombination rate, hence it is theoretically possible to increase the carrier lifetime.…”