Vol.:(0123456789) 1 3 Journal of Inorganic and Organometallic Polymers and Materials https://doi.org/10.1007/s10904-020-01765-6 Efect of Gd 3+ Doping on Linear and Nonlinear Optical Properties of PbI 2 /FTO Thin Films for Optoelectronic and Nonlinear Applications Mohd. Shkir 1  · T. Alshahrani 2  · Kamlesh V. Chandekar 3  · M. Aslam Manthrammel 1  · M. A. Sayed 1,4  · I. M. Ashraf 1,5  · Baskaran Palanivel 6  · S. AlFaify 1 Received: 18 June 2020 / Accepted: 21 September 2020 © Springer Science+Business Media, LLC, part of Springer Nature 2020 Abstract Herein, we have developed the thin Gd@PbI 2 flms on FTO via a facile spin coating route and subjected to various stud- ies. The formation of (001) oriented hexagonal phase Gd:PbI 2 /FTO flms was confrmed by X-ray difraction & FT-Raman spectroscopy analyses. The size was determined through Scherrer formula in 11–16 nm range. The doping of Gd and its homogeneity was tested and approved by EDX and SEM e-mapping studies. The Gd doping impact on surface morphology was inspected via SEM images and found very low dimension grains formation throughout the flms area. Tauc’s formula was employed to obtain energy gap and found in 2.46–2.74 eV for all Gd@PbI 2 flms. Absorption and refractive indices were estimated in 0.034–1.2 and 1.4–11 between 395 and 2400 nm wavelength regions. Respective dielectric constant and loss values were noted between 3.5 and 112, and 0.13 and 1.4, signify high dielectric constant and low loss values. The optical conductivity was calculated of 10 16 order for all Gd@PbI 2 flms. SELF and VELF related values were also determined. The values of nonlinear optics related parameters were also calculated and revealed that the grown flms are potential candidates for opto-nonlinear devices. Keywords Gd@PbI 2 /FTO thin flms · Structural and vibrational studies · Morphological properties · Optical properties · Dielectric-electrical properties · Nonlinear properties 1 Introduction The p-type semiconductor lead iodide has fascinated the research community over the years due to its fascinating properties that make it suitable for wide range of applica- tions in the felds of radiation detectors, photodetectors, medical imaging and high efciency solar cells etc. [1–4]. Ever since the emerging perovskite solar cell technology has been identifed as the biggest breakthrough research in the current era, no other samples could efciently replace the PbI 2 based photo absorber layer [5]. It has a layered structure similar to that of CdI 2 where, the Pb atoms sit in sandwiched positions between the iodine atom layers [6], and the band- gap of PbI 2 has strong dependency on the number of layers. They have been synthesized in various nanostructured forms including nanoparticles, nanotubes and many reports exist on doped PbI 2 thin flms structures. The advantage on nanostructured PbI 2 is the tunability of bandgap which can be altered by nano-growth, vary- ing the layered structure and suitable dopant according to the device-oriented optoelectronics requirement. The * Mohd. Shkir shkirphysics@gmail.com; shkirphysics@kku.edu.sa 1 Advanced Functional Materials & Optoelectronics Laboratory (AFMOL), Department of Physics, Faculty of Science, King Khalid University, Abha 61413, Saudi Arabia 2 Department of Physics, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia 3 Department of Physics, Rayat Shikshan Sanstha’s, Karmaveer Bhaurao Patil College, Vashi, Navi Mumbai 400703, India 4 Faculty of Science, Physics Department, Al-Azhar University, Assiut 71524, Egypt 5 Department of Physics, Faculty of Science, Aswan University, Aswan 81511, Egypt 6 Department of Physics and Nanotechnology, SRM Institute of Science and Technology, Kancheepuram, Tamil Nadu 603 203, India