13 research outputs found
Linear chemically sensitive electron tomography using DualEELS and compressed sensing
No abstract available
Morphology and local electrical properties of PTB7:PC<inf>71</inf>BM blends
Β© 2015 The Royal Society of Chemistry. The power conversion efficiency of single layer organic solar cells can approach 10% with blends such as the polymer PTB7 and the fullerene derivative PC71BM. Here the detailed structure of PTB7:PC71BM blends deposited with and without addition of diiodooctane is studied by transmission electron microscopy and scanning probe microscopy. The details of bulk structure, such as the thickness of the layer covering fullerene domains and the grain structure of the film are examined. We find that fullerene-rich domains can be near the surface of the film or buried deeper, near the substrate. The local electrical properties of these blends are studied by conductive atomic force microscopy for different configurations of electrodes. Different power conversion efficiencies of blends with and without diiodooctane are explained in terms of local photoconductive properties
Morphology and local electrical properties of PTB7:PC<inf>71</inf>BM blends
Β© 2015 The Royal Society of Chemistry. The power conversion efficiency of single layer organic solar cells can approach 10% with blends such as the polymer PTB7 and the fullerene derivative PC71BM. Here the detailed structure of PTB7:PC71BM blends deposited with and without addition of diiodooctane is studied by transmission electron microscopy and scanning probe microscopy. The details of bulk structure, such as the thickness of the layer covering fullerene domains and the grain structure of the film are examined. We find that fullerene-rich domains can be near the surface of the film or buried deeper, near the substrate. The local electrical properties of these blends are studied by conductive atomic force microscopy for different configurations of electrodes. Different power conversion efficiencies of blends with and without diiodooctane are explained in terms of local photoconductive properties
Morphology and local electrical properties of PTB7:PC<inf>71</inf>BM blends
Β© 2015 The Royal Society of Chemistry. The power conversion efficiency of single layer organic solar cells can approach 10% with blends such as the polymer PTB7 and the fullerene derivative PC71BM. Here the detailed structure of PTB7:PC71BM blends deposited with and without addition of diiodooctane is studied by transmission electron microscopy and scanning probe microscopy. The details of bulk structure, such as the thickness of the layer covering fullerene domains and the grain structure of the film are examined. We find that fullerene-rich domains can be near the surface of the film or buried deeper, near the substrate. The local electrical properties of these blends are studied by conductive atomic force microscopy for different configurations of electrodes. Different power conversion efficiencies of blends with and without diiodooctane are explained in terms of local photoconductive properties
Electron Tomography of Polymer Solar Cells Using Compressed Sensing
Recently, the single layer polymer solar cell (PSC) based on bulk heterojunction (BHJ) blend of two materials: fullerene derivative [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) and a polymer with alternating units of thieno{3,4βb} thiophene and benzodithiophene (PTB7) has received significant attention [1], since high power conversion efficiency (PCE) of 9.2% has been reported for devices based on this mixture [2]. Unfortunately, little is known about the nanoscale organisation of PTB7:PC71BM blends beyond some 2D imaging. In this work, we extends our previous study in [8] electron tomography (ET) [3] and a new ET image reconstruction method, DLET, to investigate the 3D organisation of such blends using. ET plays an essential role in the study of 3 dimensional (3D) nanostructures. It involves reconstructing 3D objects from a series of 2D images by sequential tilting of the sample about a single axis. This technique, although originally designed for use in the life sciences, has also been applied to the study of polymer blends using bright-Field TEM (BFTEM) as in [4]. We used energy filtered electron tomography [5] using thin cross-sections through the blend cut using a FIB (Nova Nanolab, FEI). Three-dimensional reconstruction was performed using a new compressed sensing based algorithm, DLET [6,7], which enables high-fidelity, low-noise reconstruction from relatively few projections and minimizes artifacts from the missing wedge in the tilt data. The result from DLET is also compared with traditional methods such as Weighted back projection (WBP) and simultaneous iterative reconstructive technique (SIRT). The volume rendering visualisations of the reconstructions are shown in Figure (1). EFTEM results clearly show that domains in the blend are PC71BM-rich (i.e. contain more carbon as in Fig.1(b)). The EFTEM tomography clearly reveals that these ellipsoids and are not spherical. TEM and SEM measurements of device cross-section show existence of thin skin layer covering domains
Morphology and local electrical properties of PTB7:PC<sub>71</sub>BM blends
The power conversion efficiency of single layer organic solar cells can approach 10% with blends such as the polymer PTB7 and the fullerene derivative PC71BM. Here the detailed structure of PTB7:PC71BM blends deposited with and without addition of diiodooctane is studied by transmission electron microscopy and scanning probe microscopy. The details of bulk structure, such as the thickness of the layer covering fullerene domains and the grain structure of the film are examined. We find that fullerene-rich domains can be near the surface of the film or buried deeper, near the substrate. The local electrical properties of these blends are studied by conductive atomic force microscopy for different configurations of electrodes. Different power conversion efficiencies of blends with and without diiodooctane are explained in terms of local photoconductive properties.</p
Linear chemically sensitive electron tomography using DualEELS and compressed sensing
No abstract available
Combined ultramicrotomy and atomic force microscopy study of the structure of a bulk heterojunction in polymer solar cells
Originally published in Russion, in Fizika i Tekhnika PoluprovodnikovΠ Π΄Π°Π½Π½ΠΎΠΉ ΡΠ°Π±ΠΎΡΠ΅ ΠΎΠΏΠΈΡΠ°Π½ ΠΈ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ ΡΠΏΠΎΡΠΎΠ± Π²ΠΈΠ·ΡΠ°Π»ΠΈΠ·Π°ΡΠΈΠΈ Π²Π½ΡΡΡΠ΅Π½Π½Π΅ΠΉ ΡΡΡΡΠΊΡΡΡΡ ΡΠΎΡΠΎΠ°ΠΊΡΠΈΠ²Π½ΡΡ
ΡΠ»ΠΎΠ΅Π² ΠΏΠΎΠ»ΠΈΠΌΠ΅ΡΠ½ΡΡ
ΡΠΎΠ»Π½Π΅ΡΠ½ΡΡ
Π±Π°ΡΠ°ΡΠ΅ΠΉ ΠΌΠ΅ΡΠΎΠ΄Π°ΠΌΠΈ ΡΠΊΠ°Π½ΠΈΡΡΡΡΠ΅ΠΉ Π·ΠΎΠ½Π΄ΠΎΠ²ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ, ΠΎΡΠ½ΠΎΠ²Π°Π½Π½ΡΠΉ Π½Π° ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠΈ ΡΠ»ΡΡΡΠ°ΠΌΠΈΠΊΡΠΎΡΠΎΠΌΠ° Π΄Π»Ρ ΠΏΠΎΠ»ΡΡΠ΅Π½ΠΈΡ ΡΡΠ΅Π·ΠΎΠ² ΡΠΎΡΠΎΠ°ΠΊΡΠΈΠ²Π½ΠΎΠ³ΠΎ ΡΠ»ΠΎΡ . ΠΠ°Π½Π½ΡΠΉ ΠΌΠ΅ΡΠΎΠ΄ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ ΠΏΡΠ΅ΠΈΠΌΡΡΠ΅ΡΡΠ²Π° Π°ΡΠΎΠΌΠ½ΠΎ - ΡΠΈΠ»ΠΎΠ²ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ ΠΏΡΠΈ ΠΈΠ·ΡΡΠ΅Π½ΠΈΠΈ ΡΡΡΡ ΠΊΡΡΡΡ Π² ΠΎΠ±ΡΠ΅ΠΌΠ΅ ΠΌΡΠ³ΠΊΠΈΡ
ΠΎΠ±ΡΠ°Π·ΡΠΎΠ², ΡΠ°ΠΊΠΈΠ΅ ΠΊΠ°ΠΊ Π²Ρ ΡΠΎΠΊΠΈΠΉ ΠΊΠΎΠ½ΡΡΠ°ΡΡ ΠΈΠ·ΠΎΠ±ΡΠ°ΠΆΠ΅Π½ΠΈΠΉ ΠΈ ΡΠΏΠΎΡΠΎΠ±Π½ΠΎΡΡΡ ΠΈΠ·ΠΌΠ΅ΡΡΡΡ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²Π° ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΠΈ Ρ Π½Π°Π½ΠΎΠΌΠ΅ΡΡΠΎΠ²ΡΠΌ ΡΠ°Π·ΡΠ΅ΡΠ΅Π½ΠΈΠ΅ΠΌ. ΠΠΏΠΈΡΠ°Π½Π½ΡΠΌ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ ΠΈ ΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Ρ ΠΎΠ±ΡΠ°Π·ΡΡ ΡΠΎΡΠΎΠ°ΠΊΡΠΈΠ²Π½ΠΎΠ³ΠΎ ΡΠ»ΠΎΡ ΠΏΠΎΠ»ΠΈΠΌΠ΅ΡΠ½ΠΎΠΉ ΡΠΎΠ»Π½Π΅ΡΠ½ΠΎΠΉ Π±Π°ΡΠ°ΡΠ΅ΠΈ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΡΠΌΠ΅ΡΠΈ ΠΏΡΠΎΠΈΠ·Π²ΠΎΠ΄Π½ΠΎΠΉ ΡΠΈΠΎΡΠ΅Π½Π° PTB 7 ΠΈ ΠΏΡΠΎΠΈΠ·Π²ΠΎΠ΄Π½ΠΎΠΉ ΡΡΠ»Π»Π΅Ρ Π΅Π½Π° PC 71 BM . ΠΠ±Π½Π°ΡΡΠΆ Π΅Π½Ρ Π½ΠΎΠ²ΡΠ΅ Π΄Π΅ΡΠ°Π»ΠΈ Π²Π½ ΡΡΡΠ΅Π½Π½Π΅ΠΉ ΡΡΡΡΠΊΡΡΡΡ Π΄Π°Π½Π½ΠΎΠΉ ΡΠΌΠ΅ΡΠΈ, ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡΠΈΠ΅ ΡΠ΄Π΅Π»Π°ΡΡ Π΄ΠΎΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»ΡΠ½ΡΠ΅ Π²ΡΠ²ΠΎΠ΄Ρ ΠΎ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΠ΅ Π²Π»ΠΈΡΠ½ΠΈΡ Π΄ΠΎΠ±Π°Π²ΠΎΠΊ Π΄ΠΈΠΉ ΠΎΠ΄ΠΎΠΎΠΊΡΠ°Π½Π° Π½Π° ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ ΡΠΎΠ»Π½Π΅ΡΠ½ΡΡ
ΡΠ»Π΅ΠΌΠ΅Π½ΡΠΎΠ². A method for visualization via atomic-force microscopy of the internal structure of photoactive layers of polymer solar cells using an ultramicrotome for photoactive layer cutting is proposed and applied. The method creates an opportunity to take advantage of atomic-force microscopy in structural investigations of the bulk of soft samples. Such advantages of atomic-force microscopy include a high contrast and the ability to measure various surface properties at nanometer resolution. Using the proposed method, samples of the photoactive layer of polymer solar cells based on a mixture of PTB7 polythiophene and PC71BM fullerene derivatives are studied. The disclosed details of the bulk structure of this mixture allow us to draw additional conclusions about the effect of morphology on the efficiency of organic solar cells.PostprintPeer reviewe