Surface Engineering toward High-Performance CsPbI₃ Perovskite Solar Cells

Abstract

Inorganic CsPbI3 perovskite solar cells (PSCs) have attracted intense attention due to higher chemical stability and exceptional optoelectronic properties. However, tremendous intrinsic defects in CsPbI3 perovskite have induced serious charge recombination loss, which greatly suppresses device performance. To address the issue, surface engineering has been widely used to passivate the intrinsic defects, which has well promoted the power conversation efficiency (PCE) of CsPbI3 PSCs to over 21%. In this Forum Article, recent progress in surface engineering for CsPbI3 perovskite is systematically summarized, discussed, and categorized in the following aspects: molecular modification, ion termination, in situ generation of the second phase, and direct introduction of the second phase. Finally, we present a brief outlook about challenges and opportunities of surface engineering for CsPbI3 perovskite.

High Performance Thermoelectric Power of Bi0.5Sb1.5Te3Through Synergistic Cu2GeSe3and Se Incorporations

“…[38,39] Based on the above analysis, a two-step optimization strategy is employed for the Bi 0.5 Sb 1.5 Te 3 (BST) matrix in this study, involving the introduction of Cu 2 GeSe 3 as the second phase and the utilization of Se from the neighboring VIA group of Te as the opposite codopants. Here, the selection of Cu 2 GeSe 3 is primarily driven by two factors: i) its mixed ion-electron conductor behavior contributes to higher reactivity, which also makes it easier to achieve uniform dispersion in the matrix, and thus for the elevated n H ; ii) the remarkable effects of copper-containing compounds have been extensively proven in the TE materials including but not limited to SnSe, [40] GeTe, [41] and half-Heusler alloys, [42] compared to others, its most prominent characteristic lies in the minimal adverse impact on carrier mobility (μ H ). By replacing Bi/Sb with Cu and Ge, it increases the n H and density-of-states effective mass (m d * ), leading to the net increase in weighted mobility (μ W ) and power factor (S 2 𝜎, PF).…”

In Situ Growth of a Robust 1D Capping Layer for Stable and Efficient CsPbI3 Perovskite Solar Cells Without Hole Transporter

“…However, it has been proved that extracting PbI 2 from CsPbI 3 perovskite to react with ASNI during post treatment would be hard, which may induce the phase degradation from perovskite phase to nonperovskite phase. [46] To overcome these problems, intermediate treatment (IT) was exploited, [28] in which ASNI isopropanol (IPA) solution was used to treat the DMAPbI 3 intermediate instead of treating the final CsPbI 3 perovskite film. Since the thermal stability of ASNPbI 3 is considerably higher than that of DMAPbI 3 , the decomposition of DMAPbI 3 to form CsPbI 3 perovskite at later annealing stage would not affect the pre-formed ASNPbI 3 layer if annealing temperature is proper.…”

Healing the Buried Interface by a Plant-Derived Green Passivator for Carbon-Based CsPbIBr2 Perovskite Solar Cells

“…Organic–inorganic hybrid perovskite solar cells (PSCs) have attracted extensive attention due to their unique semiconductor properties, such as long charge carrier diffusion length, tunable bandgap, high defect tolerance, and low exciton binding energies. − Within a very short time span, impressive achievements in photovoltaic applications have been made, and the certificated power conversion efficiency (PCE) of single-junction PSCs has been rapidly increased to 26.1%, which is comparable to that of Si-based solar cells. − However, the poor long-term operational stability still restricts their practical application, largely because of the usage of humidity-/heat-sensitive organic methylammonium and formamidinium. − Substituting organic cations with volatile-free Cs + to fabricate all-inorganic perovskites (CsPbX 3 , X = I, Br, Cl, or mixed) is an effective strategy to settle this issue. , Generally, there is a positive correlation between I doge and corresponding PCE owing to the reduced bandgap but a negative relationship for environmental stability. Although the efficiency of CsPbI 3 -based PSCs has exceeded 20%, the phase instability, which suffers from the phase conversion from the photoactive α-perovskite phase to the nonphotoactive β-perovskite phase, is still a great challenge for future deployment. ,, On the contrary, CsPbBr 3 exhibits the most superior stability, but its PCE is restricted by a narrower light-absorbing range .…”