Advances in design engineering and merits of electron transporting layers in perovskite solar cells

Abstract

<p>The electron transport layer plays an essential part for high-performing perovskite solar cells, on which successful extraction of charges from light harvester and the transfer to the electrode are critically dependent.</p>

2D Materials as Electron Transport Layer for Low‐Temperature Solution‐Processed Perovskite Solar Cells

“…We have found the electron transport shows less efficiency than the hole in PSCs, which causes inhomogeneous charge accumulation and serious interfacial recombination at the interface between the ETL and the perovskite active layer. [ 12 ] Therefore, it is very important to balance the charge diffusion processes in respective charge collective layers of PSCs, because the interfaces are the key to produce optical voltage and output photocurrent. [ 12 ] In this content, we need to seek several strategies by tuning the charge transfer properties at the interface for highly efficient PSCs.…”

“…[ 12 ] Therefore, it is very important to balance the charge diffusion processes in respective charge collective layers of PSCs, because the interfaces are the key to produce optical voltage and output photocurrent. [ 12 ] In this content, we need to seek several strategies by tuning the charge transfer properties at the interface for highly efficient PSCs. For instance, to increase V OC , we, thus, need to build up a functional interface with well‐matched energy bands to avoid excessive band offset while accelerating charge carrier extraction and transport.…”

“…[ 10,11 ] In generally, efficient PSCs usually have two important interfaces, e.g., ETL/perovskite heterojunction interface and perovskite/HTL interface, both of which should guarantee effective charge collection and separation. [ 12 ] A variety of charge carrier dynamics including charge transfer, charge carrier collection, and recombination at the two interfaces are shown in Figure a. Processes 1–4 illustrate the separation, transport and radiative recombination of charges carriers in the PSC device.…”

“…A high‐quality ETL not only plays a crucial role in collecting and transferring charge carriers, but can also effectively separate charges and inhibit the recombination of charge carriers, whereas inefficient charge transport could cause inhomogeneous charge accumulation and serious interfacial recombination. [ 12 ] Thence, it is urgent to design and fabricate high‐quality ETLs to ensure effective charge transfer, thus ensuring efficient photovoltaic performance of devices.…”

A Machine Learning Approach for Metal Oxide Based Polymer Composites as Charge Selective Layers in Perovskite Solar Cells

“…[3,5] Depending on the light incidence, the architect of PSCs can be either n-i-p or p-i-n type, where n-and p-type are electron and hole selective materials respectively, and i denotes to the light harvesting layer. [6] PSCs with p-i-n planar architecture display negligible hysteresis, solution processability at low temperature, and the potential for scale up using a continual coating method. [7] Fullerenes type acceptor, especially [6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM), are typically used as n-type charge transport layer [7] , while poly (3,4ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) as a transparent hole transport material in lieu of Spiro-OMeTAD, was employed.…”