The Influence of Al2O3Nanoparticles on Electron Transport in a Polymer Solar Cell

18.55% Efficiency Polymer Solar Cells Based on a Small Molecule Acceptor with Alkylthienyl Outer Side Chains and a Low-Cost Polymer Donor PTQ10

With the rapid development of society, energy consumption is increasing, and renewable clean energy is an important way to solve the problem of increasing energy consumption and how to protect the environment. Solar energy is a kind of sustainable development of clean energy. In the development of solar energy, polymer solar cells have attracted much attention due to low cost and good performance. With the deepening of research, the efficiency of polymer solar cells continues to increase, but there is still a problem of short service life, and how to improve the service life and efficiency of polymer solar cells has become a research hot spot. Since functionalized carbon nanomaterials have the advantages of good electrical conductivity, mechanical properties and strong chemical properties, this paper aims to improve the photoelectric conversion efficiency of polymer solar cells by applying functionalized carbon nanomaterials to polymer solar cells. Firstly, the working principle of solar cells was introduced. Secondly, graphene quantum dots functionalized carbon nanomaterials were prepared by hydrothermal method. Finally, graphene quantum dots are applied to polymer solar cells as acceptor materials and interface modification, and the photoelectric conversion efficiency of polymer solar cells is improved successfully. Simulation analysis shows that the prepared graphene quantum dots can improve the stability and efficiency of polymer solar cells, and play an active role in polymer solar cells.

To achieve high‐performance large‐area flexible polymer solar cells (PSCs), one of the challenges is to develop new interface materials that possess a thermal‐annealing‐free process and thickness‐insensitive photovoltaic properties. Here, an n‐type self‐doping fullerene electrolyte, named PCBB‐3N‐3I, is developed as electron transporting layer (ETL) for the application in PSCs. PCBB‐3N‐3I ETL can be processed at room temperature, and shows excellent orthogonal solvent processability, substantially improved conductivity, and appropriate energy levels. PCBB‐3N‐3I ETL also functions as light‐harvesting acceptor in a bilayer solar cell, contributing to the overall device performance. As a result, the PCBB‐3N‐3I ETL‐based inverted PSCs with a PTB7‐Th:PC71BM photoactive layer demonstrate an enhanced power conversion efficiency (PCE) of 10.62% for rigid and 10.04% for flexible devices. Moreover, the device avoids a thermal annealing process and the photovoltaic properties are insensitive to the thickness of PCBB‐3N‐3I ETL, yielding a PCE of 9.32% for the device with thick PCBB‐3N‐3I ETL (61 nm). To the best of one's knowledge, the above performance yields the highest efficiencies for the flexible PSCs and thick ETL‐based PSCs reported so far. Importantly, the flexible PSCs with PCBB‐3N‐3I ETL also show robust bending durability that could pave the way for the future development of high‐performance flexible solar cells.

Copper(І) iodide (CuI) is a very efficient inorganic p-type material and has a potential application in polymer solar cells (PSCs). However, the solution-processed CuI film tends to be rough surface morphology. Herein, CuI nanoparticles (NPs) were synthesized by water decomposing the CuI N,N-dimethylformamide (DMF) dispersion and used as hole transporting layers (HTLs) of PSCs with the configuration of ITO/CuI/P3HT:PC61BM/Ca/Al. As a result, a smooth and uniform CuI film was formed by spin coating from CuI NP acetonitrile solution. The root-mean-square roughness of the film reduced from 2.25 nm for spin coating from bulk CuI acetonitrile solution to 0.65 nm for CuI NPs. The power conversion efficiency of PSCs increased from 3.10% to 3.47% for CuI NP HTL. Moreover, the CuI NPs-based device demonstrated enhanced stability. The higher efficiency and better stability of CuI NPs-based PSCs should be attributed to uniform surface morphology and reducing exciton quenching of the CuI/the photoactive layer interface. This work indicates that CuI NPs will be a novel promising hole transporting material for highly efficient and stable PSCs.

Effect of Al2O3 nanoparticles on the performance of passive double slope solar still

ZnO:Bio-inspired polydopamine functionalized Ti3C2Tx composite electron transport layers for highly efficient polymer solar cells

High power conversion efficiency (PCE) and stretchability are the dual requirements for the wearable application of polymer solar cells (PSCs). However, most efficient photoactive films are mechanically brittle. In this work, highly efficient (PCE = 18%) and mechanically robust (crack-onset strain (COS) = 18%) PSCs are acheived by designing block copolymer (BCP) donors, PM6-b-PDMSx (x = 5k, 12k, and 19k). In these BCP donors, stretchable poly(dimethylsiloxane) (PDMS) blocks are covalently linked with the PM6 blocks to effectively increase the stretchability. The stretchability of the BCP donors increases with a longer PDMS block, and PM6-b-PDMS19k :L8-BO PSC exhibits a high PCE (18%) and 9-times higher COS value (18%) compared to that (COS = 2%) of the PM6:L8-BO-based PSC. However, the PM6:L8-BO:PDMS12k ternary blend shows inferior PCE (5%) and COS (1%) due to the macrophase separation between PDMS and active components. In the intrinsically stretchable PSC, the PM6-b-PDMS19k :L8-BO blend exhibits significantly greater mechanical stability PCE80% ((80% of the initial PCE) at 36% strain) than those of the PM6:L8-BO blend (PCE80% at 12% strain) and the PM6:L8-BO:PDMS ternary blend (PCE80% at 4% strain). This study suggests an effective design strategy of BCP PD to achieve stretchable and efficient PSCs.

The electron transport layer (ETL) in an organic solar cell is one of the main components that play a crucial role in the extraction of charges, improving efficiency, and increasing the lifetime of the solar cells. Herein, solution‐processed PBDTTT‐C‐T:PC71BM‐based organic solar cells are fabricated using conjugated PDINO molecules, sol‐gel derived under stoichiometric titanium oxide (TiOx), and a mixture of the same as an ETL. For PBDTTT‐C‐T:PC71BM‐based organic solar cells, a blend of organic‐inorganic ETLs demonstrates reduced bimolecular recombination and trap‐assisted recombination than a single ETL of either two materials. Furthermore, in both, fullerene and nonfullerene systems, the efficiency of the devices employing the blend ETL as compared to the single ETLs show some performance improvement. The strategy of integrating compatible organic and inorganic interface materials to improve device efficiency and lifetime simultaneously, and demonstrate the universality of different systems, has potential significance for the commercial development of organic solar cells.

Enhanced efficiency and stability of polymer solar cells with TiO2 nanoparticles buffer layer

Fluorinated benzothiadiazole-based low band gap copolymers to enhance open-circuit voltage and efficiency of polymer solar cells

Perylene diimide (PDI) with high electron affinities are promising candidates for applications in polymer solar cells (PSCs). In addition, the strength of π‐deficient backbones and end‐groups in an n‐type self‐dopable system strongly affects the formed end‐group‐induced electronic interactions. Herein, a series of amine/ammonium functionalized PDIs with excellent alcohol solubility are synthesized and employed as electron transporting layers (ETLs) in PSCs. The electron transfer properties of the resulting PDIs are dramatically tuned by different end‐groups and π‐deficient backbones. Notably, electron transfer is observed directly in solution in self‐doped PDIs for the first time. A significantly enhanced power conversion efficiency of 10.06% is achieved, when applying the PDIs as ETLs in PTB7‐Th:PC71BM‐based PSCs. These results demonstrate the potential of n‐type organic semiconductors with stable n‐type doping capability and facile solution processibility for future applications of energy transition devices.

The power conversion efficiency (PCE) of polymer solar cells (PSCs) can obviously be improved by plasmon resonance effects of noble metal nanoparticles. However, incorporating noble metal such as Ag and Au nanoparticles (NPs) can usually accelerate the deterioration of PSCs due to the diffusion of noble metal atoms, which would limit the potential application of plasmonic PSCs. PSCs with ferrocenedicarboxylic acid (FDA) modified Al-doped ZnO (AZO) layer compared to pure AZO layer can synchronously increase PCEs and ultraviolet (UV) and moisture stabilities. PSCs with Ag NPs doped Al-doped ZnO (AZO:Ag) increased to 10.20% of PCE from 9.08% PCE of the reference PSCs with pure AZO layer, but show inferior stability. Furthermore, PSCs with FDA modified AZO:Ag layer obtained 10.0% of PCEs and showed superior UV durability and moisture stability. PSCs with FDA modified AZO:Ag layer respectively maintain the original PCE values of 50% and 53% exposing UV light for 13 h and aging for 9 months at RH 10%, which are obviously higher than 36% and 34% of the original PCEs of PSCs with AZO:Ag layer. The results indicate that FDA modification is an effective strategy to solve the quick deterioration of plasmonic PSCs without evidently sacrificing PCEs.

Solution-processed SnO2 nanoparticle interfacial layers for efficient electron transport in ZnO-based polymer solar cells

Organic Solar Cells Based on Non-fullerene Small-Molecule Acceptors: Impact of Substituent Position

Surface roughness regulation of reduced-graphene oxide/iodine – Based electrodes and their application in polymer solar cells