Improving the Performance of Perovskite Solar Cells using a Polyphosphazene Interfacing Layer

Abstract

Herein, the impact of thin layer of polyphosphazene derivatives, as a buffer layer between the electron‐transporting layer and the back metal‐contact in mixed‐cation mixed‐halide perovskite solar cells (PSCs), is explored. PSCs with a poly[bis(allylamino)phosphazene] (PPz) interlayer exhibit enhanced rectification in the photo‐induced current density–voltage (J–V) curves, which show improved photovoltaic performance and photostability with reduced hysteresis. The thickness of the interlayer is optimized and the optimized PSCs with PPz buffer layer shows an average open‐circuit voltage (VOC) of ≈1.05 V, a short‐circuit current density (JSC) of around 23.5 mA cm−2, a fill factor of ≈72%, and a power conversion efficiency of about 17.3% for the forward and reverse scans under simulated AM1.5G illumination. Moreover, the application of PPz as an electron‐transporting interlayer in organic solar cells reveals that PPz interfacial layer improves the electron extraction at the cathode. The merit of applying PPz interlayer extends to the possibility of using different metals (such as aluminum, gold, copper, and silver) as the top contact in the prepared PCSs. In general, these experiments reveal a very promising approach to tackle the issue of interfacing, and to improve the performance and stability of PSCs.

Low-Cost Inorganic Strontium Ferrite a Novel Hole Transporting Material for Efficient Perovskite Solar Cells

“…This revealed the ambipolar charge transportation in the solar cell device vis à vis coupled electron-hole transport, which is ambipolar diffusion. It is not possible to explicitly say or predict the nature and the type of the carrier from the impedance spectra as an electrical response is symmetrical for the electrons as well as holes [20,[31][32][33][34]. The spin-resolved band structure and the total partial density of states were calculated using GGA + U, as illustrated in Figure S5.…”

“…On the other hand, at low frequencies, a typical classical behavior was noticed. The impedance spectra for solar cell devices generally have three arcs at low, intermediate, and high frequencies corresponding to dielectric relaxation, charge recombination, and selective contact charge transfer [ 20 , 31 , 32 , 33 , 34 ]. However, Figure 7 show that only two arcs were observed for low frequency and high frequency, revealing the charge transportation and separation at the interface between the perovskite (CH 3 NH 3 PbI 3 ) layer and HTL, respectively.…”

“…However, Figure 7 show that only two arcs were observed for low frequency and high frequency, revealing the charge transportation and separation at the interface between the perovskite (CH 3 NH 3 PbI 3 ) layer and HTL, respectively. The observed characteristics clearly indicate that the charge transportation is dominated by charge carriers that are further coupled with recombination across the active layer [ 20 , 31 , 32 , 33 , 34 ]. This revealed the ambipolar charge transportation in the solar cell device vis à vis coupled electron-hole transport, which is ambipolar diffusion.…”

Stability Enhancements on Methylammonium Lead‐Based Perovskite Nanoparticles: the Smart Use of Host Matrices

“…Over the last decade, metal halide perovskite‐based materials [1] have emerged a promising future in the form of semiconducting nanoparticles (NP) and nanostructures due to their unique electrical and optical properties [2] . Enhancing the current synthetic strategies for diverse low‐dimensional halide perovskite nanostructures including quantum dots (QD), nanocrystals (NC), nanowires, or nanocrystalline thin films have brought fruitful progress in optical and electronic applications, owing to their unique quantum confinement effect, high photoluminescence quantum yield (PLQY), large surface‐to‐volume ratio, and optical tenability.…”

Microwave-Assisted Preparation of Organo-Lead Halide Perovskite Single Crystals

“…Perovskites can easily be deposited from their precursor solutions into a thin film by solution-based processes. − These processes are low-cost, convenient, and efficient. Nevertheless, the prepared films possess defects that cause nonradiative recombination, current–voltage hysteresis, and rapid degradation due to the low stability of the resulting devices. ,,,− The limitations can be reduced through preparation of single crystals, which possess low trap densities, higher crystallinity, and fewer ionic defects and grain boundaries, and thus the efficiency of the resulting functional devices can increase dramatically. , There are several approaches for how a single perovskite crystal can be grown: slow evaporation, inversion temperature crystallization (ITC), modified inversion temperature crystallization, antisolvent vapor assisted, top seeded solution crystal growth, bottom seeded solution crystal growth, the temperature lowering method, and the Bridgman growth method .…”