On the Way to Optoionics

Senocrate, Alessandro; Kotomin, E. A.; Maier, Joachim

doi:10.1002/hlca.202000073

Cited by 22 publications

(19 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Under light conditions, it thus seems like the barrier preventing cation migration is released, in agreement with galvanostatic measurements from Zhao et al 39 showing decreased activation energies with increasing light intensity. This effect might happen either through an increase in the number of MA + vacancies in light—similar to the increase of halide vacancies observed in light 40 —and/or through a loosening of the Pb–X bond, perhaps upon polaron formation. 41 , 42 We also note that one of the theories behind light-induced phase segregation involves polaron stabilization of the iodide domains.…”

Section: Resultsmentioning

confidence: 92%

Reduced Barrier for Ion Migration in Mixed-Halide Perovskites

McGovern

Grimaldi

Futscher

et al. 2021

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

Halide alloying in metal halide perovskites is a useful tool for optoelectronic applications requiring a specific bandgap. However, mixed-halide perovskites show ion migration in the perovskite layer, leading to phase segregation and reducing the long-term stability of the devices. Here, we study the ion migration process in methylammonium-based mixed-halide perovskites with varying ratios of bromide to iodide. We find that the mixed-halide perovskites show two separate halide migration processes, in contrast to pure-phase perovskites, which show only a unique halide migration component. Compared to pure-halide perovskites, these processes have lower activation energies, facilitating ion migration in mixed versus pure-phase perovskites, and have a higher density of mobile ions. Under illumination, we find that the concentration of mobile halide ions is further increased and notice the emergence of a migration process involving methylammonium cations. Quantifying the ion migration processes in mixed-halide perovskites shines light on the key parameters allowing the design of bandgap-tunable perovskite solar cells with long-term stability.

show abstract

Section: Resultsmentioning

confidence: 92%

Reduced Barrier for Ion Migration in Mixed-Halide Perovskites

McGovern

Grimaldi

Futscher

et al. 2021

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

show abstract

“…Similarly, deciphering the function of hybrid perovskites for use as cathodes and anodes in rechargeable batteries and photobatteries stimulates ongoing investigations. Such developments may benefit from the emerging field of optoionics, which will further broaden research horizons (Senocrate et al, 2020).…”

Section: Discussionmentioning

confidence: 99%

Mixed Conductivity of Hybrid Halide Perovskites: Emerging Opportunities and Challenges

Futscher

Milić

2021

Front. Energy Res.

View full text Add to dashboard Cite

Hybrid halide perovskites feature mixed ionic-electronic conductivities that are enhanced under device operating conditions. This has been extensively investigated over the past years by a wide range of techniques. In particular, the suppression of ionic motion by means of material and device engineering has been of increasing interest, such as through compositional engineering, using molecular modulators as passivation agents, and low-dimensional perovskite materials in conjunction with alternative device architectures to increase the stabilities under ambient and operating conditions of voltage bias and light. While this remains an ongoing challenge for photovoltaics and light-emitting diodes, mixed conductivities offer opportunities for hybrid perovskites to be used in other technologies, such as rechargeable batteries and resistive switches for neuromorphic memory elements. This article provides an overview of the recent developments with a perspective on the emerging utility in the future.

show abstract

“…[104][105][106][107] Recent reports have so far only linked the idea that phonons contribute to ion transport, [33][34][35][36][37][38][39][40][41][42][43][44] but this is the first study showing that specific mode excitations can be used to influence diffusion in solids, which is influential to the field of lattice dynamics affecting ion transport and will most likely lead to more work on optoionics. [108][109][110] In addition, the idea that a diffusion hop can be enhanced directly by phonon excitation has far-reaching implications. If such an effect can be confirmed experimentally (see ESI for a possible approach to experimental evaluation of the reported observations in this study), it would open the door to many new possibilities.…”

Section: Discussionmentioning

confidence: 99%