2021 Nature Energy (IF 60.858): Introduction of Environmentally Friendly Green Manufacturing Process, PCE>17% Organic Solar Cells
SS-X solar simulator makes the breakthrough possible!
Top-Notch Due to It’s Precision!
Nature Energy (IF 60.858) published a study in November 2021. In the past few years, organic solar cells (OSC) have developed rapidly, mainly due to the development of non-fullerene acceptors (NFAs). In terms of power conversion efficiencies (PCEs), NFAs are based on an electron-deficient-core fused ring, also known as Y-series NFAs. Y-series NFAs can produce high PCEs over 18%. Although OSCs have commercial value, they require low-boiling-point and toxic solvents, for example, chloroform (CF)),to achieve high efficiencies. However, under the conditions of high-boiling-point and environmentally friendly solvents that industrial development hopes to use, PCEs will be significantly reduced.
Here, the research team developed a unique guest-assisted assembly strategy to simultaneously improve solubility and molecular packing in high-boiling-point solvents (including non-halogenated green solvents). The approach is to introduce a molecular BTO, which involves an amphiphilic oligo(ethylene glycol) (OEG) chain as the guest; the guest molecule BTO exhibits good solubility in high-boiling-point solvents and outstanding compatibility with the host component (Y6). The key function of the guest molecule BTO is to assist the crystalline structure of Y6.
Chemical structures and structural characterization of the acceptors.
Enlitech’s solar simulator, QE-R Quantum Efficiency Measurement system and other instruments were used in this study to assist in the measurement. It was found that under the use of environmentally friendly solvents, the PCE of OSC processed by paraxylene (PX) exceeded 17%. In addition, this method is also applicable to blade-coating a large-area OSC module (36 cm2) with a PCE of over 14%. The strong molecular interaction between the host and guest molecules also enhances the operational stability of the material. This research makes an important contribution to bring OSCs to the next stage, and can also be used to optimize other organic electronic devices.
In addition to the EQE (External Quantum Efficiency) spectrum analysis of solar cells, the Quantum Efficiency Measurement System of Enlitech also provides Jsc (short-circuit current density) comparison for the short-circuit current of solar cells under the solar simulator to prove the authenticity of the experiment. The solar simulator and KA-6000 software of Enlitech also provide monitoring of the short-circuit current over time to prove the stability of the solar cell!
Photovoltaic performance of the devices. (e) MPP stability test of unencapsulated OSCs based on PM6:Y6 (PX), PM6:Y6: 20% BTO (PX) and PM6:Y6: 20% BTO:PC71BM (PX) with initial PCEs of 11.01%, 16.41% and 17.22%, respectively, stored in N2 atmosphere under the illumination of a 100 mW cm-2 white LED.
Non-halogenated solvent-processed module and device stability. (d) Distribution of the PCEs of non-halogenated solvent-processed OSC modules in terms of device area (module area >20 cm2).
Keywords: organic solar cell, guest-assisted assembly strategy, green solvent, Solar Simulator, Quantum Efficiency, Sun Simulator
Article link: https://doi.org/10.1038/s41560-021-00923-5