Ramifications of Ion Migration in 2D Lead Halide Perovskites

Mathew, Preethi; Cho, Junsang; Kamat, Prashant V.

doi:10.1021/acsenergylett.4c00093

Cited by 12 publications

(2 citation statements)

References 109 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Based on the kinetics of phase segregation, photo-induced phase segregation is due to the migration of halide ions [91,92] . If ion migration is suppressed, phase segregation becomes difficult [93] .…”

Section: Application Of the Database In Perovskite Segregation Studymentioning

confidence: 99%

Data-driven strategy for bandgap database construction of perovskites and the potential segregation study

Wu,

Zhang,

Wang

et al. 2024

J Mater Inf

View full text Add to dashboard Cite

Light-induced segregation limits the practical application of mixed halide perovskites in solar cells. Herein, halide segregation is evaluated by a data-driven approach with constructing a bandgap database of 53,361 mixed ABX3 [where A = Cs, formamidinium (FA) or methylammonium (MA); B = Pb or Sn; X = Br, Cl, or I] perovskites. A transfer learning strategy was employed to fine-tune the parameters of a Graph Neural Network model using experimental and density functional theory (DFT)-calculated bandgaps. This approach accelerated the construction of a unique database, distinguishing it from others primarily focused on ABX3 perovskite element substitution. The database is characterized by continuously varying compositions and accurate bandgaps. It was utilized to calculate the free energy of 20,688 mixed iodine-bromine perovskites and generate corresponding phase diagrams for predicting their light-induced segregation behavior. It is found that the bandgap increases with decreasing ionic radii at the A-site and X-site. This composition-dependent bandgap difference drives halide segregation. Moreover, using a higher Cs content at the A-site, rather than MA, reduces this bandgap difference, enhancing photostability. The proposed data-driven strategy can facilitate the targeted design of novel perovskites with mixed compositions and the investigation of halide perovskite segregation.

show abstract

Section: Application Of the Database In Perovskite Segregation Studymentioning

confidence: 99%

Data-driven strategy for bandgap database construction of perovskites and the potential segregation study

Wu,

Zhang,

Wang

et al. 2024

J Mater Inf

View full text Add to dashboard Cite

show abstract

“…The primary mechanism for this is through halide vacancies that exhibit low activation energies in the MHP lattice both intrinsically and under the influence of external stimuli such as heat and light. The consequences of ion migration are phase separation and electrochemical reactions with transport layers and electrodes, affecting their extraction properties that induce material degradation and electronic losses [7,[10][11][12][13] . It has been shown in our previous work that ion migration in PSCs and MHPs can be quantified in terms of a mobile ion concentration (N o ) [6] .…”

Section: Introductionmentioning

confidence: 99%

Use of carbon electrodes to reduce mobile ion concentration and improve reliability of metal halide perovskite photovoltaics

Penukula,

Tippin,

et al. 2024

Energy Mater

View full text Add to dashboard Cite

Ion migration is one of the prime reasons for the rapid degradation of metal halide perovskite solar cells (PSCs), and we report on a method for quantifying mobile ion concentration (No) using a transient dark current measurement. We perform both ex-situ and in-situ measurements on PSCs and study the evolution of No in films and devices under a range of temperatures. We also study the effect of device architecture, top electrode chemistry, and metal halide perovskite composition and dimensionality on No. Two-dimensional perovskites are shown to reduce the ion concentration along with inert C electrodes that do not react with halides by ~99% while also improving mechanical reliability by ~250%. We believe this work can provide design guidelines for the development of stable PSCs through the lens of minimizing mobile ions and their evolution over time under operational conditions.

show abstract

X‐ray‐ultraviolet–visible‐near‐infrared photoresponses realized in a lead‐free hybrid perovskite ferroelectric through light‐induced ferro‐pyro‐phototronic effect

Fu,

Ma,

et al. 2024

InfoMat

View full text Add to dashboard Cite

Due to the built‐in electric field induced by spontaneous polarization in hybrid perovskite (HP) ferroelectrics, the devices based on them exhibit excellent performance in self‐powered photodetection. However, most of the self‐powered photodetector are made of lead‐based HP ferroelectrics and have a relatively narrow photoresponse waveband. Although lead‐free HPs solve the problem of lead toxicity, their optoelectronic performance is inferior to that of lead‐based HPs and photoresponse waveband is limited by its optical band gap, which hinders their further application. To solve this problem, herein, a lead‐free HP ferroelectric (HDA)BiI5 (HDA is hexane‐1,6‐diammonium) with large spontaneous polarization shows an enhanced photocurrent and achieves x‐ray‐ultraviolet–visible‐near‐infrared (x‐ray‐UV–Vis–NIR) photoresponse through the ferro‐pyro‐phototronic (FPP) effect. The ferroelectric, pyroelectric, and photovoltaic characteristics coupled together in a single‐phase (HDA)BiI5 ferroelectric is an effective way to improve the performance of the devices. What is particularly attractive is that the FPP effect not only improves the optoelectronic performance of (HDA)BiI5, but also achieves broadband photoresponses beyond its optical absorption range. Especially, the current boosting with an exceptional contrast of ~1100% and 2400% under 520 and 637 nm, respectively, which is associated with FPP effect. Meanwhile, single crystal self‐powered photodetector based on (HDA)BiI5 also exhibit significant FPP effects even under high‐energy x‐ray, which owns an outstanding sensitivity of 170.7 μC Gy−1 cm−2 and a lower detection limit of 266 nGy s−1 at 0 V bias. Therefore, it is of great significance to study the coupling of multiple physical effects and improve device performance based on lead‐free HP ferroelectrics.image

show abstract

Ramifications of Ion Migration in 2D Lead Halide Perovskites

Cited by 12 publications

References 109 publications

Data-driven strategy for bandgap database construction of perovskites and the potential segregation study

Data-driven strategy for bandgap database construction of perovskites and the potential segregation study

Use of carbon electrodes to reduce mobile ion concentration and improve reliability of metal halide perovskite photovoltaics

X‐ray‐ultraviolet–visible‐near‐infrared photoresponses realized in a lead‐free hybrid perovskite ferroelectric through light‐induced ferro‐pyro‐phototronic effect

Contact Info

Product

Resources

About