Ways to Improve the Performance of Triple‐Mesoscopic Hole‐Conductor‐Free Perovskite‐Based Solar Cells

Abstract

Hybrid perovskite is an attractive semiconductor material being used intensively in photovoltaic cells for the last 10 years. It can be integrated in several architectures of solar cells, which are based on the concept that the perovskite is sandwiched between an electron selective contact and a hole‐selective contact capped by a metal electrode as the back contact. An additional and unique solar cell structure is the mesoporous layers solar cell, which is based on mesoporous TiO2 following by mesoporous ZrO2 (or Al2O3) and capped by mesoporous carbon or recently by mesoporous indium tin oxide (ITO) electrodes. These solar cells are fabricated by screen printing and the perovskite is applied in the last step by infiltration through the three mesoporous layers. This solar cell structure holds a great promise, due to its fabrication techniques, high stability, and recycling process. In this review, several ways are brought together to improve the performance of these cells, using additives for the different layers, posttreatments, and ways to change the energy level positions to enhance the photovoltaic performance. Also, a new concept of replacing the carbon with a mesoporous ITO electrode is presented, which shows promising results. The review ends with summary and outlook.

Printing Perovskite Solar Cells in Ambient Air: A Review

“…[57,58] In the PSC industry, this printing technique is easily applied to the printing of mesoporous scaffolds such as mesoporous titanium oxide (m-TiO 2 ) and mesoporous zirconium oxide (m-ZrO 2 ), or carbon electrodes onto conductive glass, thus constituting an attracting technology for the industrialization of PSC. [59] Nevertheless, the low viscosity and poor stability of perovskite inks constitute major issues hindering the fabrication of screen-printed PSC devices. Notably, Han et al [60] successfully fabricated a full screen-printed mesoporous PSC device (1 μm mesoporous TiO 2 as ETL, a 2 μm mesoporous ZrO 2 as spacer layer, and a 10 μm mesoporous carbon black/graphite as top electrode).…”

SnS Quantum Dots Enhancing Carbon-Based Hole Transport Layer-Free Visible Photodetectors

“…These dangling bonds form defect recombination centers, causing significant non-radiative recombination of photogenerated carriers at this interface and severe loss of photocurrent [ 18 , 19 ]. Furthermore, the energy-level mismatch between the carbon electrode and perovskite impairs the hole extraction efficiency of the devices [ 20 ]. To improve the interface contact between the carbon electrode and the perovskite layer, a strategy involving the integration of additives into the carbon electrode has been suggested.…”

Quantum Dot Bridges Enabling Highly Efficient Carbon‐Based Hole Transport Material‐Free Perovskite Solar Cells

“…However, along with all the provided benefits, such a device structure brings new vulnerabilities like poor contact at the perovskite/carbon interface and inefficient hole collection/extraction owing to the misalignment of energy levels at the perovskite/carbon interface. [ 3 ]…”

“…However, along with all the provided benefits, such a device structure brings new vulnerabilities like poor contact at the perovskite/carbon interface and inefficient hole collection/extraction owing to the misalignment of energy levels at the perovskite/carbon interface. [3] Since the first carbon-based HTM-free PSC with an efficiency of 6.64% was reported by Han et al in 2013, considerable efforts have been made for the improvement of charge transport at the interface between perovskite layer and carbon back electrode. [4] One efficient way to enhance the power conversion efficiency (PCE) of carbon-based HTM-free PSCs through interface optimization is to control the nucleation and growth of perovskite film for achieving high-quality absorber layer in PSCs.…”