Magnetic Properties in CH₃NH₃PbI₃ Perovskite Thin Films by Mn Doping

Abstract

In recent years, perovskite halide compounds have attracted attention for the fabrication of highly efficient solar cells, light-emitting diodes, and X-ray detection. However, a comprehensive understanding of their microscopic origins has not been fully explored. In this work, the effect of Mn doping in organic–inorganic perovskite semiconductor methylammonium lead iodide (CH3NH3PbI3) has been studied. The existence of magnetism in CH3NH3PbI3 (MAPbI3) has been confirmed by magnetization measurements at room temperature. A drastic enhancement in magnetic moment is obtained in Mn (15%)-doped MAPbI3. The influence of Mn doping in MAPbI3 films has been analyzed for structural and morphological changes. Room-temperature ferromagnetism is achieved by the incorporation of Mn2+/Mn3+ ions into Mn (3–20%)-doped MAPbI3 films by the effect of eminent double-exchange and superexchange interactions in between the Mn2+–I – –Mn3+ ions compared with other doping content. Our finding offers an alternative pathway for spintronic, light-controlled magnetic and photovoltaic devices.

Ferromagnetism and Spin-Polarized Luminescence in Lead-Free CsEuCl3 Perovskite Nanocrystals and Thin Films

“…Ferromagnetic ordering of Eu 2+ spins is observed with T C = 2.5–3.0 K. The similar magnetic hystereses and ordering temperatures in nanocrystals and thin films indicate that this ferromagnetism is intrinsic to bulk CsEuCl 3 . Importantly, all Eu 2+ participate in this ferromagnetic ordering, contrasting CsEuCl 3 with the several magnetically doped metal-halide perovskite and related semiconductors recently reported to show ferromagnetism; − in the latter, the magnetic ions are present at relatively low concentrations (compared to CsEuCl 3 ) and only minority populations appear to order ferromagnetically. Those materials are thus arguably better described as metal-halide perovskites containing ferromagnetic inclusions or domains, whereas CsEuCl 3 is a bona fide ferromagnetic metal-halide perovskite.…”

“…Previous reports of magnetic perovskites have relied on open-shell dopants such as Mn 2+ or Fe 3+ to impart magnetic functionality. In some cases, ferromagnetic ordering is observed but with small magnetic moments that indicate its origin in ferromagnetic domains or inclusions, with the majority of the dopant population remaining paramagnetic. − Some observations have demonstrated weak coupling between such magnetism and the optical properties of the materials . Further advances in the development of magnetic metal-halide perovskites will generate attractive opportunities to access spin-controlled electronic and photonic properties, or photon-controlled spin properties, in this versatile class of materials.…”

Magnetism in a 2D Hybrid Ruddlesden–Popper Perovskite through Charge Redistribution Driven by an Organic Functional Spacer

“…However, the magnetic moment resulting from the spin–orbit coupling compared to the exchange magnetic interaction is weak, preventing their application in magneto-optical devices. More recently, the range of applications of a hybrid perovskite has been expanding, and the phenomena related to spin-polarized electronic transport in spintronic or energy-related devices have been addressed including spin–orbit coupling. , In this type of approach, spin injection, accumulation, transport, and detection at room temperature by the manipulation of dopants are often reported. , A straightforward alternative approach to achieving magnetism is through magnetic ion doping such as Fe, Mn, and Co into the semiconducting perovskite structure. − This approach has played an important role to electronics and spintronics in conventional semiconductors, but the incorporation of extrinsic dopants introduces disorder and defects into the electronic structure. We have recently reported Fe ions incorporated into MAPbI 3 perovskite microwires introducing magnetic degrees of freedom into the system but at the cost of suppressing the mobility of charge carriers as well as photoluminescence quenching …”

A mechanistic study of the dopant-induced breakdown in halide perovskites using solid state energy storage devices

“…For example, the insertion of ions with an active spin, such as manganese, has been shown to create magnetically active HP semiconductors. 51,52 The insertion of Li has also been proposed to improve the performance of LED devices by tailoring the energy levels at the interface between the charge insertion layers and the emitting perovskite layer, thus improving the electron insertion efficiency and reducing the turn-on voltage. 14,53 The findings of this work aim to provide a quantitative framework within which these device performance enhancements may be harnessed.…”

“…In addition to the substitution of A or B ions in the HP, adding species that sit interstitially within the structure have recently been shown to engender interesting material effects. For example, the insertion of ions with an active spin, such as manganese, has been shown to create magnetically active HP semiconductors 51,52 . The insertion of Li has also been proposed to improve the performance of LED emitting perovskite layer, thus improving the electron insertion efficiency and reducing the turn-on voltage 14,53 .…”