Low-Cost Silicon Phthalocyanine as a Non-Fullerene Acceptor for Flexible Large Area Organic Photovoltaics

Abstract

We demonstrate large-area (1 cm 2 ) organic photovoltaic (OPVs) devices based on bis(tri-n-butylsilyl oxide) silicon phthalocyanine (3BS) 2 -SiPc as a non-fullerene acceptor (NFA) with low synthetic complexity paired with poly(3-hexylthiophene) (P3HT) as a donor polymer. Environment-friendly nonhalogenated solvents were used to process large area OPVs on flexible indium tin oxide (ITO)-coated polyethylene terephthalate (PET) substrates. An alternate sequentially (Alt-Sq) blade-coated active layer with bulk heterojunction-like morphology is obtained when using (3BS) 2 -SiPc processing with o-xylene/1,3,5-trimethylbenzene solvents. The sequential (Sq) active layer is prepared by first blade-coating (3BS) 2 -SiPc solution followed by P3HT coated on the top without any post-treatment. The conventional sequentially (Sq) blade-coated active layer presents very low performance due to the (3BS) 2 -SiPc bottom layer being partially washed off by processing the top layer of P3HT. In contrast, alternate sequentially (Alt-Sq) blade-coated layer-by-layer film shows even better device performance compared to the bulk heterojunction (BHJ) active layer. Time-of-flight secondary ion mass spectroscopy (TOF-SIMS) and atomic force microscopy (AFM) reveal that the Alt-Sq processing of the active layer leads to a BHJ-like morphology with a well-intermixed donor−acceptor component in the active layer while providing a simpler processing approach to low-cost and large-scale OPV production.

Structure–Property Relationship of Macrocycles in Organic Photoelectric Devices: A Comprehensive Review

“…Furthermore, in 2023, Lessard et al prepared a flexible, large-area (1 cm 2 ) organic photovoltaics device based on low-cost silicon phthalocyanine (41f) as a nonfullerene acceptor. The PCE of this device was 1.3% [189].…”

Effect of Direct Alkyne Substitution on the Photophysical Properties of Two Novel Octasubstituted Zinc Phthalocyanines

“…By using 4,5 or 3,6-disubstituted starting materials, a single isomer can be obtained because mono-substituted phthalonitrile derivatives cause a mixture of isomers. [6,7,9,10,14,22,23] The functionality of the Pc can be altered by the formation of a CÀ C bond that binds directly to the Pc ring by crosscoupling reactions. Although there are studies in the literature on Pc carrying a terminal alkyne group, studies on the synthesis of compounds bearing the alkyne group directly linked to the Pc ring are extremely limited.…”

“…The use of isomeric mixtures is not preferred because it causes difficulties in the reproducibility of photochemical, photophysical, and biological measurements. By using 4,5 or 3,6‐disubstituted starting materials, a single isomer can be obtained because mono‐substituted phthalonitrile derivatives cause a mixture of isomers [6,7,9,10,14,22,23] …”

“…[ 2 , 3 ] Numerous information about their synthesis, photophysical, and photochemical properties have been revealed since their discovery in 1907. [ 1 , 2 , 4 ] They are now industrially prepared and used as dyes and colorants and a lot of patents and reports have been published for their application as liquid crystals, [5] boron neutron capture therapy,[ 6 , 7 ] electrochromic compounds, [8] nonlinear optical materials, [9] photovoltaic cells, [10] chemical sensors [11] and catalysts in organic synthesis. [12] The photophysical properties of Pcs are of great interest because they exhibit very strong absorption peaks at longer wavelengths in the far‐red region of the visible spectrum than porphyrins.…”

Sustainable Photooxidation using a Subpart-per-million Heavy-Metal-Free Red-Light Photocatalyst

“…Si-phthalocyanines are commercially available PSs with a high extinction coefficient in the red and NIR range due to an intense Q-band centered around 670 nm. Si-phthalocyanine properties have been found to be useful for numerous applications, such as photodynamic therapy − or organic photovoltaics. − In addition, they can be heterogenized on graphene or silica with applications in hydrogen evolution or 1 O 2 production . Thus, they could represent interesting sustainable alternatives to perform photochemical reactions under red/NIR light where their utilization is still underexplored .…”