Charge carrier dynamics and self-trapping on Sb2S3(100)

A comprehensive insight into deep-level defect engineering in antimony chalcogenide solar cells

“…The self-trapping model rationalizes the high V OC -deficits in Sb 2 S 3 solar cells, pinning the upper limit of the V OC at 0.8 V and PCE at 16%. Grad et al 35 performed time-resolved two-photon photoemission experiments to study the photoexcited carrier dynamics in single-crystal Sb 2 S 3 . They proposed a model of self-trapping of free charge carriers by optical phonons and the formation of intrinsic traps.…”

“…However, it is conceivable that there is ambiguity regarding the self-trapping in Sb 2 Se 3 and Sb 2 (S,Se) 3 and the extent to which it impedes carrier transport in these materials. 35,40 The suppressed or nonexistent self-trapping in Sb 2 Se 3 and Sb 2 (S,Se) 3 facilitates improved charge transport, which is reflected in their better device performance than their Sb 2 S 3 counterparts (Table S1, ESI †). Notably, the upper limit of the V OC (B0.8 eV) projected by the self-trapping model for Sb 2 S 3 solar cells was experimentally reported by Maity et al 41 and Peng et al 42 In this regard, any further improvement in V OC will provide evidence for the validity and efficacy of this model.…”

A Review of Carrier Transport in High‐Efficiency Sb2(S,Se)3 Solar Cells

“…The trapped carriers cannot be saturated even with the injection of up to 10 20 cm −3 , which are too large to be related to external impurities or defects, but from self‐trapping due to lattice distortion (Figure 3e). Grad et al [ 42 ] further investigated charge‐carrier dynamics and the trapping mechanism in Sb 2 S 3 with energy and momentum resolution conducted by time‐resolved two‐photon photoemission. The presence of both free and trapped electrons in the CB and observed gap state coincide with the picture of self‐trapping.…”

Ten Years of Sb2Se3 Thin Film Solar Cells

“…[2,45] Later, the result was directly confirmed by experimental measurement and DFT calculations. [46] Mobility of the absorbers is very important for solar cells because it determines the carrier diffusion length and thereby the absorber thickness. But the mobility of Sb 2 Se 3 is inconclusive for a long time.…”

“…[ 2,45 ] Later, the result was directly confirmed by experimental measurement and DFT calculations. [ 46 ]…”