Isomerism Strategy to Optimize Aggregation and Morphology for Superior Polymer Solar Cells

Shen, Xiangyu1; Lai, Xue1,2; Lai, Hanjian1,2; Zhao, Tingxing1; Zhu, Yulin1,2; Pu, Mingrui1; Wang, Hengtao1; Tan, Pu1; He, Feng1,3

2022-07-01

10.1021/acs.macromol.2c00837

MACROMOLECULES   Impact Factor & Quartile

0024-9297

1520-5835

The effect of isomerism in polymer donors is appealing as a means of optimization of molecular configurations in organic solar cells (OSCs) but has not been well explored. Two isomers, PAB-alpha and PAB-gamma, with different orientations of their fused thiophene rings were designed and synthesized to investigate the influence of isomerism in polymer donors on their photovoltaic conversions. It was shown that two polymers with almost identical structures exhibited significant differences in the power conversion efficiency (PCE) of solar devices. The PAB-alpha-based devices achieve an excellent PCE of 15.05%, while the PAB-gamma-based devices only obtain an extremely low PCE of 0.04%. Reasons for such a dramatic performance disparity include first, the absorption spectrum of PAB-gamma being markedly blue-shifted and failing to match the absorption spectrum of common high-efficiency acceptors, such as Y6, and second, acceptor Y6 has preferable miscibility with PAB-alpha for a smaller chi value of 0.067 and smaller root-mean-square value of 0.98 nm. What is more, PAB-alpha has a closer pi-pi interaction distance compared to its isomer PAB-gamma from grazing-incidence wide-angle X-ray scattering (GIWAXS) analysis, and the order-of-magnitude difference between the hole and electron mobilities of two active layers also made the opposing values of their device efficiencies. Therefore, PAB-alpha has a superior performance in photovoltaic devices, demonstrating that fine tuning of atomic orientation could bring great changes to the properties of the polymer donors. This provides a new train of thought for the material design and evolution of device performance.

SCI ; EI

English

NI Journal Papers

First ; Corresponding

National Natural Science Foundation of China["21975115","21733005"] ; Shenzhen Fundamental Research Program["JCYJ20210324120010028","JCYJ20190809163011543","JCYJ20200109140801751"] ; Guangdong Innovative and En- trepreneurial Research Team Program[2016ZT06G587] ; Guangdong Provincial Key Laboratory of Catalysis[2020B121201002] ; Shenzhen Sci-Tech Fund[KYTDPT20181011104007]

Polymer Science

Polymer Science

WOS:000831798700001

AMER CHEMICAL SOC

20223312579787

Absorption spectroscopy ; Efficiency ; Electromagnetic wave absorption ; Morphology ; Organic solar cells ; Plants (botany) ; Red Shift ; Stereochemistry ; X ray scattering

Solar Cells:702.3 ; Electromagnetic Waves:711 ; Light/Optics:741.1 ; Chemistry:801 ; Chemical Products Generally:804 ; Production Engineering:913.1 ; Physical Properties of Gases, Liquids and Solids:931.2 ; High Energy Physics:932.1 ; Materials Science:951

CHEMISTRY

Web of Science

1.Southern Univ Sci & Technol, Shenzhen Grubbs Inst, Dept Chem, Shenzhen 518055, Peoples R China
2.Harbin Inst Technol, Sch Chem & Chem Engn, Harbin 150001, Peoples R China
3.Southern Univ Sci & Technol, Guangdong Prov Key Lab Catalysis, Shenzhen 518055, Peoples R China

Shen, Xiangyu,Lai, Xue,Lai, Hanjian,et al. Isomerism Strategy to Optimize Aggregation and Morphology for Superior Polymer Solar Cells[J]. MACROMOLECULES,2022,55:6384-6393.

Shen, Xiangyu.,Lai, Xue.,Lai, Hanjian.,Zhao, Tingxing.,Zhu, Yulin.,...&He, Feng.(2022).Isomerism Strategy to Optimize Aggregation and Morphology for Superior Polymer Solar Cells.MACROMOLECULES,55,6384-6393.

Shen, Xiangyu,et al."Isomerism Strategy to Optimize Aggregation and Morphology for Superior Polymer Solar Cells".MACROMOLECULES 55(2022):6384-6393.