Layer-edge device of two-dimensional hybrid perovskites

• Published in: Nature communications Vol. 9; no. 1; pp. 5196 - 7
• Main Authors: Cheng, Bin, Li, Ting-You, Wei, Pai-Chun, Yin, Jun, Ho, Kang-Ting, Retamal, José Ramón Durán, Mohammed, Omar F., He, Jr-Hau
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 05.12.2018; Nature Publishing Group; Nature Portfolio
• Subjects: 147/3; 639/301; 639/301/119; Conductance; Crystallography; Dark current; Humanities and Social Sciences; Humidity; Hydroxyl groups; multidisciplinary; Optoelectronic devices; Perovskites; Photovoltaic cells; Photovoltaics; Resistance; Science; Science (multidisciplinary); Solar cells; Superlattices; Thickness; Water chemistry
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-018-07656-2

Two dimensional layered organic-inorganic hybrid perovskites (2D perovskites) are potential candidates for next generation photovoltaic device. Especially, the out-of-plane surface perpendicular to the superlattice plane of 2D perovskites (layer-edge surface) has presented several exotic behaviors, such as layer-edge states which are found to be crucial for improving the efficiency of 2D perovskite solar cells. However, fundamental research on transport properties of layer-edge surface is still absent. In this report, we observe the electronic and opto-electronic behavior in layer-edge device of 2D perovskites. The dark and photo currents are demonstrated to strongly depend on the crystallographic orientation in layer-edge device, and such anisotropic properties, together with photo response, are related to the thickness of inorganic layers. Finally, due to the abundant hydroxyl groups, water molecules are easy to condense on the layer-edge surface, and the conductance is extremely sensitive to the humidity environment, indicating a potential application of humidity sensor. The edge of the thin sheets of two dimensional organic-inorganic hybrid perovskite crystals shows exotic physical properties that remain unexplored. Here Cheng et al. make electronic devices and study their transport properties, photoresponses and humid sensitivities which show large anisotropy.