Nanoscale properties of lead halide perovskites by scanning tunneling microscopy

Abstract

Since the introduction of lead halide perovskites, tremendous progress has been made regarding their stability, reproducibility and durability. However, one of the issues that remains is related to the interfacial atomic structure arrangement and structure-property relationship under optical and electrical stimuli. In this critical review, we highlight the recent progress using scanning tunneling microscopy (STM) to understand the nanoscale properties and dynamic processes occurring in these halide perovskite materials. STM is known to be a very challenging technique, which is reflected by the low number of relevant publications in the last years. These initial reports mirror the unique potential of STM to give Ångstrom-scale insight into the (opto)electronic properties, morphology and underlying electronic structure and provide a path toward harnessing the full potential of these materials. However, care must be taken to understand the effects of the perturbations caused by STM and tailor the measurement conditions accordingly.

Defect Passivation of Mn2+-Doped CsPbCl3 Perovskite Nanocrystals as Probed by Scanning Tunneling Spectroscopy: Toward Boosting Emission Efficiencies

“…In this direction, scanning tunneling spectroscopy (STS) has been considered as an efficient tool in probing the band edges and mid-gap states as well. The ability to probe the density of states (DOS) with energy and spatial resolutions has made this technique unique in various quantum dots and complex core–shell systems. − …”

Atomic Level Insights into Metal Halide Perovskite Materials by Scanning Tunneling Microscopy and Spectroscopy

“…Dedicated mechanistic studies of the conversion process remain scarce, and the main reason for this is that it is very difficult to achieve high temporal resolution and atomic resolution simultaneously. The combination of STM with a laser provides a viable solution to in situ probing of various atomic‐scale dynamics in MHPM, such as optical absorption, photoelectric conversion, charge dynamics, electron‐phonon coupling, etc [13c,d, 18d,e, 50, 68] . With this advanced technique, it is possible to gain insights into the internal mechanism of photovoltaics, which is of great importance for the development of PSCs, as this will provide useful guidelines for the design of high‐efficiency MHPM‐based photovoltaic devices.…”

Viewing Optical Processes at the Nanoscale: Combining Scanning Tunneling Microscopy and Optical Spectroscopy

“…In this Perspective, we highlight the recent progress of SMA-STM to investigate light–matter interactions, starting with one of the very first investigated systems: CNTs and QDs. For the interested reader, additional review articles on optical STM can be found in refs − . We further show how the development of the SMA-STM technique has been extended to expand the classes of materials that can be investigated by SMA-STM, including CDs, clusters, and thin films.…”