Investigation of the electronic, optical and magnetic properties of a novel two-dimensional lead-free perovskite: High visible-light absorption and long-range magnetic ordering

• Published in: Journal of alloys and compounds 2024-12, Vol.1007, p.176450, Article 176450
• Main Authors: Mhadhbi, Noureddine, Msalmi, Rawia, Mosconi, Edoardo, Erwann, Jeanneau, Khmissi, Hammadi, Orendáč, Martin, Čižmár, Erik, Naïli, Houcine
• Format: Article
• Language: English
• Subjects: Band gaps; Lead-free perovskite; Magnetic properties; Photovoltaic; Stability
• ISSN: 0925-8388
• DOI: 10.1016/j.jallcom.2024.176450

Recently, big issues that need to be solved in photovoltaic solar cells area are the toxicity and instability of lead halide perovskites which have shown exceptional photoelectric performances. Herein, we report the synthesis and physico-chemical characterization of a novel two-dimensional (2D) lead-free perovskite. The 2D Cu(II)-based perovskite (C4N3H16)[CuCl4]∙Cl was successfully stabilized by the slow evaporation method under room temperature. The X-ray diffraction shows a layered structure with an inorganic network formed by four corners sharing CuCl6 octahedra. The UV-Vis absorption analysis confirms the manifestation of the cooperative Jahn-Teller effect around the Cu(II) ions. In addition to the ligand-to-metal charge transfer transitions, crystal field transitions (d-d) enhance the visible-light absorbance and make the material suitable for green solar cell applications with a band gap energy of 2.17 eV. The thermal analysis revealed the thermal stability of (C4N3H16)[CuCl4]∙Cl. Magnetic measurements revealed the presence of dominant ferromagnetic exchange interactions with J/kB = 22.85 K within the 2d planes, with a weak antiferromagnetic exchange interaction yielding a long-range magnetic ordering at 12 K. [Display omitted] •Crystal and molecular structure of newly synthesized material ((DET)[CuCl4]∙Cl) have been determined.•Structural and magnetic properties are correlated.•The band gap energy was found to be 2.17 eV.•The optical behavior of the investigated material indicates it may be a strong candidate for green solar cell applications.