Touching is believing: interrogating halide perovskite solar cells at the nanoscale via scanning probe microscopy

Abstract

Halide perovskite solar cells based on CH 3 NH 3 PbI 3 and related materials have emerged as the most exciting development in the next generation photovoltaic technologies, yet the microscopic phenomena involving photo-carriers, ionic defects, spontaneous polarization, and molecular vibration and rotation interacting with numerous grains, grain boundaries, and interfaces are still inadequately understood. In fact, there is still need for an effective method to interrogate the local photovoltaic properties of halide perovskite solar cells that can be directly traced to their microstructures on one hand and linked to their device performance on the other hand. In this perspective, we propose that scanning probe microscopy (SPM) techniques have great potential to realize such promises at the nanoscale, and highlight some of the recent progresses and challenges along this line of investigation toward local probing of photocurrent, work function, ionic activities, polarization switching, and chemical degradation. We also emphasize the importance of multi-modality imaging, in-operando scanning, big data analysis, and multidisciplinary collaboration for further studies toward fully understanding of these complex systems.

Promoting the Hole Extraction with Co3O4 Nanomaterials for Efficient Carbon‐Based CsPbI2Br Perovskite Solar Cells

“…The KPFM is regarded to be an effective way to map the contact potential distribution on the local grain boundaries and grain bulk . To investigate the effect of the inserted Co 3 O 4 HTM on the local electrical properties of perovskite layer at nanoscale level, the average contact potential difference (CPD) was studied under light and in the dark by KPFM.…”

Probing of Local Multifield Coupling Phenomena of Advanced Materials by Scanning Probe Microscopy Techniques

“…Raman measures the scattered photons, while IR measures the adsorption. AFM‐IR has been applied in the studies of CH 3 NH 3 PbI 3 hybrid perovskite solar cells to reveal its chemical heterogeneity and ferroelasticity, while AFM‐Raman has been widely used in polymers characterizations . The two newly developed techniques and related applications were recently reviewed by Fu and Zhang …”

Thinning ferroelectric films for high-efficiency photovoltaics based on the Schottky barrier effect

“…The ferroelectric photovoltaic (PV) effect has gained widespread attention in the past decade [1][2][3][4][5] because of its promising applications in solar energy harvesting [6][7][8] , selfpowered photodetection 9,10 , and information storage 11,12 . Ferroelectric PVs exhibit many appealing features that are unavailable in conventional PVs, such as switchable photoresponse 13,14 , above-bandgap photovoltage 15 , and light polarization-dependent photocurrent 16 .…”