- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Organogels Based on PEDOT:PSS and Carbon‐dots for Efficient Hole Transport in Organic Photovoltaics
摘要： Organic photovoltaic devices (OPVs) have received great attention in the past decades for next-generation renewable energy sources due to the low production cost and ?exible structure. The structure of OPVs is commonly composed of anode, hole transport layer (HTL), photoactive layer, and cathode. In general, an electrically conducting polymer such as poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is used as the HTL to improve interfacial properties between the anode and photoactive layer. The PEDOT:PSS consists of hydrophobic and conductive PEDOT-chains doped with hygroscopic insulator PSS, resulting in poor electrical properties. It has been known that treatment of PEDOT:PSS with polar organic solvent or acid and annealing caused the conformational change and thus improved the electrical conductivity. However, controlling the orientation and shape of the PEDOT in PEDOT:PSS is still a challenge for improving the electrical percolation pathway. Recently, the electrical conductivity of PEDOT:PSS has been enhanced by inducing the gelation of PEDOT through self-assembly with graphene oxide (GO) and/or graphene quantum dots (GQDs). Although the gelation of PEDOT:PSS improved its mechanical, thermal, and electrical properties, its morphological changes and gelation mechanism in thin ?lms have not been well understood. In this letter is described the development of reticulated charge–transporting networks with enhanced electrical properties of self-assembled PEDOT:PSS organogels containing carbon-dots. Carbon-dots acted as a physical linker with PEDOT-chains in PEDOT:PSS through electrostatic interactions, resulting in the formation of a core–shell (carbon-dot@PEDOT) nanostructure. Furthermore, the blending ratio of carbon-dots and PEDOT:PSS and the gelation time affected the organogel ?lm morphology of a nanostructure which is associated with their electrical properties. The resulting carbon-dot@PEDOT:PSS organogel ?lms were applied as an HTL for typical poly(3-hexylthiophene) (P3HT): [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) bulk heterojunction (BHJ) OPVs. As a result, the power conversion ef?ciency (PCE) of OPVs was enhanced by 30% due to the improvement of the electrical percolation pathway of the PEDOT:PSS ?lms.
关键词： PEDOT:PSS,Hole transport,Carbon-dots,Organic photovoltaics,Organogel
更新于2025-09-12 10:27:22
-
Precursor-Mediated Synthesis of Shape-controlled Colloidal CsPbBr <sub/>3</sub> Perovskite Nanocrystals and their Nanofiber-Directed Self-assembly
摘要： Shape control is often necessary to tune the optical and electronic properties of nanocrystals (NCs) and is mostly achieved through manipulation of surface ligands and processing conditions. Here we present a versatile synthesis of colloidal CsPbBr3 perovskite NCs of various shapes (nanorods, nanocubes and nanoplatelets) from an inexpensive steroidal Cs precursor: cesium cholate (CsCh). Cesium cholate has several advantages over the most commonly used Cs-precursor (cesium oleate or Cs2CO3 or CsOAc) such as low-cost, non-hygroscopicity and better reproducibility in the perovskite synthesis. Due to the solubility of this Cs-precursor in polar solvents such as methanol, a miniscule polar environment is created during the nucleation and growth of the nanocrystals leading to the serendipitous formation of nanorods at 180 ℃, whereas using a biphasic mixture of 1-octadecene and methanol, the morphology changes to nanocubes. By lowering the reaction temperature (90 ℃), nanoplatelets with 8-9 monolayers thicknesses are formed. These colloidal NCs of variety of shapes are strongly luminescent with a green emission having narrow emission linewidths (16-17 nm) and high quantum yields (96% for nanocubes, 94% for nanoplatelets). Furthermore, hybrid materials of nanocubes and organogel of a dimeric bile acid-derived ester gelator are obtained through co-assembly in which nanocubes arrange along nanofibers with stable, sharp and bright green emission. This enables spatial ordering of nanocubes ranging from micron to centimeter scale in thin films, which is crucial for advanced optoelectronic applications. To date, there is no report in literature on the anisotropic organization of perovskite CsPbBr3 nanocubes triggered by supramolecular co-assembly involving organogel nanofibers.
关键词： nanocubes,organogel,Shape control,hybrid materials,nanorods,cesium cholate,nanoplatelets,supramolecular co-assembly,colloidal CsPbBr3 perovskite NCs
更新于2025-09-12 10:27:22