Honeycomb‐Type TiO₂ Films Toward a High Tolerance to Optical Paths for Perovskite Solar Cells

Abstract

Given the advantages of high power conversion efficiencies (PCEs), antisolvent-step free production, and suitability for device production in ambient conditions, perovskite solar cells (PSCs) based on ionic-liquid solvents have attained particular research interest. To further improve device performance, light management could be optimized to increase light harvesting in the perovskite layer. Here, ordered honeycomb-like TiO 2 (Hc-TiO 2 ) structures with a periodicity of around 450 nm were fabricated through a sacrificial template method. With this photonic crystal structure, the control to light flow and the confinement effect for perovskite growth were achieved simultaneously in the Hc-TiO 2 , leading to improved light absorption as well as preferred crystal orientation. Furthermore, a reduced trap-state density and a well-aligned energy level induced by the perovskite/pore interlayer facilitated the chargecarrier extraction from the perovskite layer to electron transport layer. As a result, the structured devices performed better than the planar cells. And the angular dependent J-V sweeps show that the structured device reserved 76 % of its initial short circuit current density (J sc ), whereas the planar cell showed more than a half loss under the incident light of 40°, demonstrating a reduced downward trend in J sc with the presence of photonic crystal structures. This occurrence also suggests that the structured PSCs in this work have a high tolerance to optical path changes.

Unraveling the modification effect at NiOx/perovskite interfaces for efficient and stable inverted perovskite solar cells

“…According to the literature, the growth of perovskite crystals is closely related to the substrate surface, 41 and an ordered crystal orientation with a large grain size along the (110) direction is believed to have a positive effect on the charge carrier transport. 42 The UV/vis absorption spectra of the perovskite lms are shown in Fig. 3A.…”

Photonic Crystal Structures for Photovoltaic Applications

“…In the case of 3D structures, only inverse opal structures resulting from relatively cheap technology based on self-assembly are taken into account [ 189 ]. In the literature, the following techniques to produce SC prototypes are proposed: chemical vapor deposition [ 179 ], physical vapor deposition [ 103 ], spin coating [ 187 ], reactive-ion etching (RIE) [ 12 ], nano-imprinting techniques [ 184 ], and atomic layer deposition (ALD) [ 189 ]. However, the balance of production costs and benefits should be considered.…”

Rapid Joule heating synthesis of Ni doped into porous honeycomb C3N4 with greatly improved photocatalytic H2 production

“…Due to the introduction of pores in the structure of HCN samples, the incident light was reflected multiple times inside the pores, which enhanced the light trapping ability of the HCN samples over the entire spectral range. 41,66 The increased NVs after Joule heating significantly affected the electronic structure and photon trapping ability of the C 3 N 4 materials, and possibly provided additional active sites for photocatalysis, 67 resulting in a significant enhancement of the absorption of HCN-V N . Owing to the moderate doping of Ni, Ni/HCN-V N exhibited wider light absorption, which improved the utilization of light by the material, and thus facilitated the photocatalytic hydrogen production reaction.…”