Page 67 - Read Online

Page 12 of 16 Dong et al. Energy Mater. 2026, 6, 600026

Figure 6. (A) Mott-Schottky plots (1/C -V), (B) N C-V curves, (C) Nyquist plots, (D and E) space-charge-limited current (SCLC)
2
measurements of W/O and W Nd samples, (F) light-intensity dependence of V OC .

NdCl treatment decreases, while the charge transfer resistance (R ) value increases, indicating enhanced
3
rec
carrier transport and inhibited carrier recombination. Figure 6D and E shows the space-charge-limited
current (SCLC) dark logarithmic J-V curves of the two devices. The calculated onset voltages in the
trap-filled limit (TFL) region (V ) for the untreated and treated devices are 0.54 and 0.32 V, respectively.
TFL
The defect density was calculated according to Supplementary Note 6 based on the V analysis.
TFL

The extracted N values for the control and Nd-doped Sb Se films are 2.98 × 10 and 1.76 × 10 cm ,
-3
14
14
trap
2
3
respectively. The reduced trap density in the Nd-doped Sb Se film indicates a lower concentration of
3
2
electrically active defects, which is consistent with the suppression of trap-assisted recombination . As
[53]
shown in Figure 6F, the slope obtained from the linear fitting is mainly associated with trap-assisted
Shockley-Read-Hall (SRH) recombination. Compared with the control device, the NdCl -treated device
3
exhibits a significantly lower slope, suggesting that SRH recombination is effectively suppressed, thereby
contributing to improved device performance [54,55] . To further evaluate the stability of Sb Se solar cells,
2
3
additional aging tests were conducted under controlled conditions with a temperature of 25 °C and a relative
humidity of 35% ± 5% [Supplementary Figure 13]. Compared with the control device, the NdCl -treated
3
Sb Se device demonstrates a longer carrier lifetime and a more stable PCE. This behavior reflects more
3
2
efficient charge extraction and collection, as well as a reduced recombination rate in the NdCl -treated Sb Se 3
2
3
film [56,57] . Overall, these results demonstrate that Nd doping effectively reduces defect density, suppresses
charge recombination, and enhances carrier separation and transport, leading to improved efficiency and
stability of Sb Se solar cells.
3
2
CONCLUSIONS
In summary, this study proposes an Nd-based ionic antisite diffusion strategy to regulate the growth and
interfacial properties of Sb Se thin films. The controlled diffusion of Nd contributes to enhanced structural
3
2
order, regulated orientation and grain evolution, reduced defect-related disorder, and a more favorable