Photoluminescence enhancement and high accuracy patterning of lead halide perovskite single crystals by MeV ion beam irradiation

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2020, Vol.8 (29), p.9923-993
• Main Authors: Palei, Milan, Motapothula, M, Ray, Aniruddha, Abdelhady, Ahmed L, Lanzano, Luca, Prato, Mirko, Panda, Jaya K, Scarpellini, Alice, Pellegrini, Vittorio, Primetzhofer, Daniel, Petralanda, Urko, Manna, Liberato, Dang, Zhiya
• Format: Article
• Language: English
• Subjects: Correlation analysis; Crystal defects; Energy dissipation; Fluorescence; Ion beams; Ion probes; Lead compounds; Metal halides; Optical properties; Optoelectronic devices; Penetration depth; Perovskites; Photoluminescence; Radiation damage; Radiative recombination; Single crystals; Surface defects
• ISSN: 2050-7526; 2050-7534; 2050-7534
• DOI: 10.1039/d0tc02326d

Focused ion beam (FIB) has recently been used to tune the optical properties of lead halide perovskites (LHPs), opening an interesting avenue for applications in optoelectronic devices. However, it has remained an open question to date whether FIB can be used to locally enhance the photoluminescence (PL) of LHPs. In this work we irradiate MAPbBr 3 (MA = methylammonium) single crystals with a high energy micron-sized ion probe of different ionic masses (3 MeV He + , 12.5 MeV Br 5+ , and 20 MeV I 7+ ) and study the PL as a function of the damage induced by the ion beam. We find that at low damage levels the PL is enhanced about six times with respect to the pristine material, while increasing the damage level produces a progressive PL decrease, and, above a threshold, the PL is finally quenched below the value of the pristine crystal. We attribute this behavior to the interaction of free carriers with irradiation induced surface defects: at low damage levels the migration of carriers toward the bulk is inhibited via trapping-detrapping events at surface defects, allowing their radiative recombination near the surface; at higher damage, though, the probability for non-radiative recombination increases and gradually becomes dominant. We thus present a method to locally increase the PL of bulk LHP, which could be applied in a wide range of fields, such as highly sensitive ion beam detection or future optoelectronic device design. Using MeV ion irradiation, a PL enhancement effect of MAPbBr 3 single crystals is demonstrated.