Efficiency enhancement in P3HT-based polymer solar cells with a NaYF4:2% Er3+, 18% Yb3+ up-converter

Abstract

The commonly used donor material poly(3-hexylthiophene) (P3HT) confines the power conversion efficiency (PCE) in P3HT-based polymer solar cells due to its relatively large bandgap of $1.9 eV and the resultant limited absorption wavelength region of less than 650 nm. In this communication, the highly efficient up-conversion (UC) material NaYF 4 :2% Er 3+ , 18% Yb 3+ , converting near-infrared radiation into green and red emissions, is introduced into a P3HT/P3HT:[6,6] phenyl C 61 butyric acid methyl ester (PC 61 BM) bulk heterojunction solar cell, referred to as a "bilayer cell", to compensate for the nonabsorbable wavelength region of P3HT. With an optimal UC doping concentration of 11.7% (weight ratio of UC to P3HT) in the P3HT matrix, the short-circuit current density and PCE for UC-doped bilayer cell are as high as 10.89 mA cm À2 and 3.62%, about 16.6% and 10.7% higher than the P3HT/ P3HT:PC 61 BM bilayer cell and 22.4% and 16.4% higher than the standard P3HT:PC 61 BM bulk heterojunction one, respectively, although the fill factor in the UC-doped bilayer cell shows a slight decrease. The research result demonstrates that both the emission and the scattering of UC nanoparticles are beneficial to the enhancement of the solar cell's electrical performances.

Recent advances in energy transfer in bulk and nanoscale luminescent materials: from spectroscopy to applications

“…237 Under 980 nm excitation, the photocurrent increases by 100% as compared to the reference cell without the UC layer. 244 4.2.2 UC enhanced photocatalysis and artificial photosynthesis. Similar experiments has been demonstrated by Chen et al using 980 nm laser as the excitation light, and the enhancement in NIR response and conversion efficiency have also been observed.…”

Improved Efficiency of Inverted Perovskite Solar Cells Via Surface Plasmon Resonance Effect of Au@PSS Core‐Shell Tetrahedra Nanoparticles

“…Surface plasmon resonance (SPR) effect has been found to be a fascinating solution to improve light absorption in solar cells by utilizing strong local field and light scattering generated by metallic nanoparticles (NPs) or periodic metal nanostructures . To date, metallic NPs have been widely utilized in almost all types of solar cells, for example, dye‐sensitized and organic solar cells (OSCs), due to advantages of well‐dispersion of metal NPs in a variety of aqueous/organic solutions and the easy control over NPs’ shape, size, and density .…”

Concentration dependence of the up- and down-conversion emission colours of Er3+-doped Y2O3: a time-resolved spectroscopy analysis

“…Lanthanide doped up-conversion (UC) materials, which can convert infrared radiation into visible luminescence via excited state absorption (ESA) or energy transfer (ET) to excited states, have been widely investigated since their discovery in the 1960s [1-3]. Lanthanide doped UC materials can be used for a variety of applications [2], ranging from biology to solar conversion; the narrow visible emission excited by low energy can be employed in biomedicine [4], solid state laser [5] and illumination [6], and the materials can be implemented in a functional phosphor layer to improve the efficiency of solar cell by means of converting infrared light, which cannot be absorbed by solar cell, into absorbable visible light [7][8].…”

“…1–3 Lanthanide doped UC materials can be used for a variety of applications, 2 ranging from biology to solar conversion; the narrow visible emission excited by low energy can be employed in biomedicine, 4 solid state laser 5 and illumination, 6 and the materials can be implemented in a functional phosphor layer to improve the efficiency of solar cells by means of converting infrared light, which cannot be absorbed by solar cells, into absorbable visible light. 7,8…”

“…Although the energy of the excitation and emission bands, due to optical transitions within the 4f n energy manifolds, is weakly dependent on the lanthanide ion's surroundings, changes in the host matrix may affect the emission intensity as well as the UC routes. Lanthanide based UC halides, 6,7,9–18 glasses 19–21 and oxides 8,22–38 have been studied both for a basic understanding of the underlying physics and for a number of applications. However, it has been a challenge to find the most chemically stable and efficient material.…”