TY - JOUR
T1 - Solvent engineering for two-dimensional perovskite of guanidium lead iodide
AU - Nath, Narayan Chandra Deb
AU - Kang, Hyeong Cheol
AU - Lee, Jae Joon
N1 - Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2022/12
Y1 - 2022/12
N2 - Guanidinium lead tri-iodide-based perovskite (GAPbI3) is considered a potential candidate for stable structural template of future perovskite solar cells (PSCs) due to the high molecular symmetry of the GA cation, leading to a near-zero dipole moment, along with a high thermodynamic stability. However, a very low power conversion efficiency (PCE) has been reported for GAPbI3 PSC due to its low-dimensionality, comparatively large band gap, and significant trap states due to large grain boundaries and severe aggregation. In the present study, a two-dimensional (2D) GA2PbI4 perovskite is prepared via a one-step Lewis acid–base adduct approach in which a 7:3 ratio of 4-tert-butylpyridine (tBP) and thiourea in dimethylformamide is employed as the Lewis base. It is observed that the tBP promotes the layer-by-layer growth of 2D perovskite in two directions by guiding multiple PbI2 layers more effectively. The optimized GA2PbI4 perovskite film exhibits better uniformity, large grain size, reduced trap states, and a lower band gap of 2.03 eV. The device containing the GA2PbI4 perovskite exhibits a PCE of ca. 1.74%, along with long-term durability under ambient conditions, and hysteresis-free current density-voltage behavior. The significant enhancement in the PCE of the GA cation-based PSC leaves scope for further improvement in the perovskite-based devices.
AB - Guanidinium lead tri-iodide-based perovskite (GAPbI3) is considered a potential candidate for stable structural template of future perovskite solar cells (PSCs) due to the high molecular symmetry of the GA cation, leading to a near-zero dipole moment, along with a high thermodynamic stability. However, a very low power conversion efficiency (PCE) has been reported for GAPbI3 PSC due to its low-dimensionality, comparatively large band gap, and significant trap states due to large grain boundaries and severe aggregation. In the present study, a two-dimensional (2D) GA2PbI4 perovskite is prepared via a one-step Lewis acid–base adduct approach in which a 7:3 ratio of 4-tert-butylpyridine (tBP) and thiourea in dimethylformamide is employed as the Lewis base. It is observed that the tBP promotes the layer-by-layer growth of 2D perovskite in two directions by guiding multiple PbI2 layers more effectively. The optimized GA2PbI4 perovskite film exhibits better uniformity, large grain size, reduced trap states, and a lower band gap of 2.03 eV. The device containing the GA2PbI4 perovskite exhibits a PCE of ca. 1.74%, along with long-term durability under ambient conditions, and hysteresis-free current density-voltage behavior. The significant enhancement in the PCE of the GA cation-based PSC leaves scope for further improvement in the perovskite-based devices.
KW - Guanidium Lead Triiodide, Diguanidinium lead tetra-iodide
KW - Lewis acid-base adduct
KW - Perovskite solar cell
KW - Two-dimensional
UR - http://www.scopus.com/inward/record.url?scp=85137689746&partnerID=8YFLogxK
U2 - 10.1016/j.synthmet.2022.117175
DO - 10.1016/j.synthmet.2022.117175
M3 - Article
AN - SCOPUS:85137689746
SN - 0379-6779
VL - 291
JO - Synthetic Metals
JF - Synthetic Metals
M1 - 117175
ER -