Flexible All‐Solution‐Processed Organic Solar Cells with High‐Performance Nonfullerene Active Layers

Abstract

All‐solution‐processed organic solar cells (from the bottom substrate to the top electrode) are highly desirable for low‐cost and ubiquitous applications. However, it is still challenging to fabricate efficient all‐solution‐processed organic solar cells with a high‐performance nonfullerene (NF) active layer. Issues of charge extraction and wetting are persistent at the interface between the nonfullerene active layer and the printable top electrode (PEDOT:PSS). In this work, efficient all‐solution‐processed NF organic solar cells (from the bottom substrate to the top electrode) are reported via the adoption of a layer of hydrogen molybdenum bronze (HXMoO3) between the active layer and the PEDOT:PSS. The dual functions of HXMoO3 include: 1) its deep Fermi level of −5.44 eV can effectively extract holes from the active layer; and 2) the wetting issues of the PEDOT:PSS on the hydrophobic surface of the NF active layer can be solved. Importantly, fine control of the HXMoO3 composition during the synthesis is critical in obtaining processing orthogonality between HXMoO3 and the PEDOT:PSS. Flexible all‐solution‐processed NF organic solar cells with power conversion efficiencies of 11.9% and 10.3% are obtained for solar cells with an area of 0.04 and 1 cm2, respectively.

Novel Bimodal Silver Nanowire Network as Top Electrodes for Reproducible and High‐Efficiency Semitransparent Organic Photovoltaics

“…Recently, various TCEs as solution‐processed alternatives have been investigated, such as metallic nanowires, [ 14–16 ] conductive polymers, [ 17,18 ] carbon nanotubes, [ 19,20 ] and graphene. [ 21,22 ] Among these materials, silver nanowires (AgNWs) have been considered the most promising candidate, due to their ability to construct thin interconnected networks with benchmark transparency of 80–90% in the visible wavelength range yet highly conductive properties of 10–100 Ω □ −1 sheet resistance ( R sh ).…”

Secondary Bonds Modifying Conjugate‐Blocked Linkages of Biomass‐Derived Lignin to Form Electron Transfer 3D Networks for Efficiency Exceeding 16% Nonfullerene Organic Solar Cells

“…Nonfullerene acceptors (NFAs) organic solar cells (OSCs) have been attracting extensive investigation in the past few years owing to the advantages of their tunable energy levels, regulated region of absorption, high absorptive coefficient, and adjustably molecular structures. [ 1–6 ] So far, the champion power conversion efficiencies (PCEs) of single‐junction and tandem NFAs‐OSCs approach 17.4% and 17.3% with optimized devices, as well as in‐depth understanding on the interfacial modification. [ 7,8 ] However, the traditional interfacial materials, working effectively for fullerene based OSCs, are ineffective for the NFAs‐OSCs due to the impeded electron transfer in all directions of NFAs' conformational anisotropy.…”

Robust metal ion-chelated polymer interfacial layer for ultraflexible non-fullerene organic solar cells

“…rganic solar cells (OSC) have been attracting great attentions due to their easy processing and increasing power conversion efficiency (PCE) [1][2][3][4][5][6][7][8][9][10][11] . Comparing to inorganic counterparts, the organic and polymer semiconductors have excellent mechanical flexibility which enables the fabrication of ultraflexible and stretchable organic optoelectronic devices [12][13][14] .…”