High-performance semitransparent organic solar cells enabled by pseudo-planar heterojunction structures combined with optical engineering

Ding, Yang; Zhang, Rui; Shi, Yu; Guo, Xia; Zhang, Maojie

doi:10.1039/d2tc02689a

Cited by 7 publications

(8 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Transparent organic solar cells (T-OSCs), in particular, have advantages such as lightweight, transparency, solution processability, and mechanical flexibility, and they can be applied to building-integrated photovoltaics (BIPVs) or smart window technologies. − To evaluate the performance of T-OSCs applied to windows, various parameters, such as the average photopic transmittance (APT), power conversion efficiency (PCE), and color rendering index (CRI), are utilized. ,, In particular, the APT, which is the brightness of an object as perceived by the human eye, is crucial because a higher APT can reduce electricity consumption while maintaining interior brightness and improve the quality of human life by providing an external view . However, since the APT and PCE have a trade-off relationship, research is required to increase the APT while maintaining a certain level of PCE. , …”

Section: Introductionmentioning

confidence: 99%

“…6 However, since the APT and PCE have a trade-off relationship, research is required to increase the APT while maintaining a certain level of PCE. 7,8 The formation of transparent top electrodes with a high APT and a low sheet resistance on photoactive layers has been considered the most challenging technical barrier in developing T-OSCs with both a high APT and a high PCE. 9−11 To overcome this barrier and fabricate efficient T-OSCs, pioneering researchers have explored various transparent top electrodes, including conducting polymers, silver nanowires, graphene, transparent conducting metal oxides, carbon nanotubes, and hybrids thereof.…”

Section: ■ Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Photopically Transparent Organic Solar Cells with Tungsten Oxide-Based Multilayer Electrodes

Oh,

Kim,

Kim

et al. 2023

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

The tailoring of the average photopic transmittance (APT) of transparent organic solar cells (T-OSCs) has been the greatest challenge in building-integrated photovoltaic applications for future smart solar windows to regulate indoor brightness, maintain a human circadian rhythm, and positively impact human emotions by allowing the observation of the external environment. However, a notorious trade-off exists between the APT and power conversion efficiency (PCE) of T-OSCs, mainly due to the absence of highly conductive and transparent top electrodes, which are a key building block determining the PCE and APT. Herein, we demonstrate a new tungsten oxide (WO 3 )-based multilayer as a highly conductive and transparent top electrode that provides an excellent APT while maintaining a high PCE in T-OSCs. With the assistance of optical simulation based on a transfer matrix method to calculate the optimum thicknesses of the multilayer electrodes, we achieve the best-performing T-OSC with a PCE of 7.0% and a full device APT of 46.7%, resulting in a high light utilization efficiency of 3.27%, which is superior to that of T-OSCs based on the same photoactive system. Furthermore, superior thermal stability at 85 °C in an N 2 atmosphere is observed in WO 3based T-OSCs, maintaining 98% of the initial PCE after about 231 h. Our findings provide new insights into the development of T-OSCs with high efficiency and transparency.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

Photopically Transparent Organic Solar Cells with Tungsten Oxide-Based Multilayer Electrodes

Oh,

Kim,

Kim

et al. 2023

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…24 the device structure engineering enhances the PCEs without compromising their AVT, such as conducting polymer interlayer 25 and electrode modification with antireflection coating. 26,27 Herein, we demonstrate a strategy, using vertically stacked multiheterojunctions, to realize highly transparent and efficient ST-OPVs. 28,29 These vertical multiheterojunctions introduce cascading alignments of the lowest unoccupied molecular orbitals (LUMOs) and highest occupied molecular orbitals (HOMOs) to facilitate efficient charge extraction and transport in parallel to the device structure direction.…”

Section: Introductionmentioning

confidence: 99%

“…As an unfortunate consequence, ST-OPVs are often plagued by a trade-off between their PCEs and their average visible transmittances (AVTs). , Previously, we demonstrated that ST-OPVs incorporating sequentially deposited pseudo p – i – n active layers can successfully circumvent this trade-off between the AVT and PCE, with substantially improved performance over those of traditional ST-OPVs featuring BHJ active layers . Moreover, the device structure engineering enhances the PCEs without compromising their AVT, such as conducting polymer interlayer and electrode modification with antireflection coating. , …”

Section: Introductionmentioning

confidence: 99%

High-Efficiency Semitransparent Organic Photovoltaics Containing Vertical Multiheterojunctions

Chang

Lin

Tan

et al. 2022

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

Although semitransparent organic photovoltaics (ST-OPVs) are attractive components of various building-integrated photovoltaic applications, there is an intrinsic trade-off in their power conversion efficiencies (PCEs) and average visible transmissions (AVTs)because the photocurrent generated usually requires substantial absorption in the visible light that determines transmission. In this paper, we describe a vertically stacked tunable multiheterojunction strategy toward highly efficient ST-OPVs that simultaneously maintain high AVTs. The vertical triheterojunctions of the active layer comprise one polymer donor, D18, and two small molecule acceptors, Y1 and Y6, that were formed with a sequentially deposited (SD) method. The triheterojunction structures not only introduced cascading energy levels of their lowest unoccupied molecular energy levels that aligned in parallel to the charge extraction direction but also can be tuned by varying their relative thicknesses, thereby significantly improving charge transport in the ST-OPVs without severely suffering AVT losses. We demonstrate the universality and broad tunability of this technique for balancing the PCEs and AVTs of the devices. Our ST-OPVs achieved champion PCEs as high as 13.9% at an AVT of 22.8% (100 nm active layer with deposited trilayers having D18, Y1, and Y6 at 45, 5, and 50 nm, respectively) and 13.5% at an AVT of 23.8% (100 nm active layer with deposited trilayers having D18, Y1, and Y6 at 40, 10, and 50 nm, respectively), while the PCE of the device with a bulk heterojunction (BHJ) D18/Y6 (1:1 wt) active layer at 100 nm is 12.3% at an AVT of 17.0%. Relative to the conventional BHJ devices, the PCEs of the both types of SD trilayer devices increased by at least 10%, while the AVTs increased by at least 25%, indicating the effectiveness of the vertical multiheterojunction structures. These efficiencies of the SD trilayer devices are among one of the best records for such ST-OPVs at comparable AVTs.

show abstract

“…Promotion of BHJ ST-OPVs has fallen into bottleneck.Recently, pseudoplanar heterojunction (PPHJ) structure shows great potential application in ST-OPVs. [22][23][24][25] Donor and acceptor have gradient distribution in PPHJ structure. It was proved that PPHJ structure ensures efficient dissociation and diffusion of excitons as well as charge transporting.…”

mentioning

confidence: 99%

Low Temperature Sequential Deposition Strategy for High Performance Pseudoplanar Heterojunction Semitransparent Organic Photovoltaics

Fan

Guo

et al. 2023

Advanced Optical Materials

View full text Add to dashboard Cite

neck of the balance between photoharvest PCE and average visible transmittance (AVT). Series of strategies have been proposed to improve the PCE and AVT, such as ternary strategy with ultranarrow bandgap materials as the third component, [13] adjusting the thickness of active layers to balance the AVT and PCE, [14] adjusting the weight ratio of donor to acceptor, [15] layer-by-layer strategy, [16] and so on. [17][18][19][20][21] Besides, optimizing morphology of active layer was another efficient strategy to improve performance. Song et al. reported BHJ OPVs with PCE of 18.01% by solvent annealing. ST-OPVs were fabricated with same strategy with PCE of 13.07% at AVT of 19.33%. [7] Although the performance of opaque devices is greatly improved, the corresponding strategies applied to translucent devices have not achieved good results. The key reason is that BHJ structure requires donor (D) and acceptor (A) keeping fixed ratio, for minor adjustment of D:A ratio will have a great impact on interpenetrating networks and result in low performance. Thus, with high visible absorbance polymer donor, it is hard to realize enhancement of AVT with slight PCE loss. Promotion of BHJ ST-OPVs has fallen into bottleneck.Recently, pseudoplanar heterojunction (PPHJ) structure shows great potential application in ST-OPVs. [22][23][24][25] Donor and acceptor have gradient distribution in PPHJ structure. It was proved that PPHJ structure ensures efficient dissociation and diffusion of excitons as well as charge transporting. [26,27] In theory, slight reduction of donor thickness will get higher AVT with slight PCE loss. Hao et al. reported sequential deposition (SD) processing PPHJ ST-OPVs with PCE of 12.22% and AVT of 22.2%. [25] Their research also proved that as thickness of the active layer reduced, PCE of PPHJ devices decrease slower than BHJ devices, which means that it is valid to optimize PPHJ devices by only optimizing donor. SD is the most common strategy to form PPHJ structure. Most researchers deposit acceptor on donor film, where donor and acceptor molecular diffuse together at the interface region to form conventional PPHJ structure. [28,29] To ensure valid molecular diffusion, the solvent of top layer should have proper solubility for bottom layer. SD process is strongly affected by many factors, such Semitransparent organic photovoltaics (ST-OPVs) have great application potential in photovoltaic buildings and wearable devices. Studies have proved that power conversion efficiency (PCE) and average visible transmittance (AVT) reveal more balanced in pseudoplanar heterojunction (PPHJ) structure than in bulk heterojunction (BHJ) structure. An interesting approach named low temperature sequential deposition (LTSD)-spin-coating the small molecule acceptor (A) Y6 on polymer donor (D) PM6-is proposed to form an efficient PPHJ structure. In the LTSD process, small molecule Y6 will diffuse through amorphous PM6 layer which means that Y6 finally aggregates at the bottom of active layer and results in vertical gradient concentrat...

show abstract

High-performance semitransparent organic solar cells enabled by pseudo-planar heterojunction structures combined with optical engineering

Abstract: Semitransparent organic solar cells (ST-OSCs) are emerging as a promising renewable energy technology for building integration. However, how to solve the trade-off between power-conversion efficiency (PCE) and average visible transmittance...

Cited by 7 publications

References 65 publications

Photopically Transparent Organic Solar Cells with Tungsten Oxide-Based Multilayer Electrodes

Photopically Transparent Organic Solar Cells with Tungsten Oxide-Based Multilayer Electrodes

High-Efficiency Semitransparent Organic Photovoltaics Containing Vertical Multiheterojunctions

Low Temperature Sequential Deposition Strategy for High Performance Pseudoplanar Heterojunction Semitransparent Organic Photovoltaics

Contact Info

Product

Resources

About