Doctor blade method

Two methods are applicable for preparing 2 thin films One is the doctor blade method and the other is the screen-printing method. 

Coating Doctor blade method Coating R Screen-printing method. 

Choi et al. successfully dispersed CNTs with different contents in Nafion solution to form homogeneous composites [27]. Then CNT/Nafion composite films were prepared by doctor blade method. SEM images suggested that the SWNTs were homogeneously dispersed in the Nafion matrix, indicating that wrapping of the SWNTs by the Nafion in an aqueous solution is effective. Hewitt etal. prepared the PVDF/CNT composite film with different content of CNTs by adding PVDF into the CNTs dimethylacetamide (DMAC) solution [28]. 

In general, electrode paint is prepared by mixing water or NMP with the active material, the binder, and other additives (such as thickener or conductive carbon). The paint is then applied to the collector using the doctor-blade method and so on, and then dried, pressed, and cut to prepare electrodes. The properties of the electrode paint and electrodes themselves change according to the type of active material and additives used. Therefore, the composition must be optimized to the conditions under which the paint is applied to the collector. 

Degussa P25 Ti02 FTO Doctor blade method Pt/carbon black 20%EtOH+0.2MNaOH 20% glycerol + 0.2 M NaOH Single- and two-compartment cell Ethanol, glycerol etc. 450 WXe lamp Antoniadou etal (2010)... 

The basic manufacturing process for multilayer ceramic substrates is shown in Figure 1.3 [16]. First, the ceramic powder and organic binder are mixed to make a milky slurry. The slurry is cast into tape using the doctor blade method, to obtain a raw ceramic sheet (green sheet) that before firing, is flexible like paper. Vias for conduction between layers and wiring patterns... 

With the doctor blade method, the shear rate is determined by the speed of the carrier film and the blade gap. hi general the viscous behavior of ceramic slurry is as shown in Figure 6-3. As the shear rate increases, viscosity falls. Since the gradient of viscosity is low with regard to the shear rate, the greater the shear rate the lower the variation in viscosity becomes. It follows that if the speed of the carrier film is increased and the blade gap is deaeased, the viscosity of the slurry when it comes into contact with the casting head can be stabilized which is effective for controlling the thickness of the sheet. 

K. Otsuka, Y. Osawa and K. Yamada, Studies on Conditions in Casting Alumina Ceramics by the Doctor-Blade Method and their Effects on the properties of Green Sheets (Part 1) J. Ceram. Soc. Jpn., Vol. 94, No. 3, (1986), pp. 351-359. 

Fig. 1 Examples of morphologies of semiconductor nanostructures, (a) metal assisted Si etching and formation of Si-NWs. Electrochemical formation of (b) microporous silicon, (c) ZnO nanorods, (d) porous CdSe using porous alumina template, (e) CdTe nanowires using alumina template, (1) CdS nanowires using alumina template, (g) mesoporous Xi02 film using doctor blade method, (h) self-ordered anodic Xi02 nanotubes and (i) cross section image of the same Xi02 nanotubes (reproduced with permission from Ref. 8,27,28,45 8).

In the same period, an alcohol-based WO3 nanoparticle suspension method was demonstrated by Stubhan et al to function as an HTL in OSCs with both normal and inverted device architectures. The suspension of 7 nm particle size WO3 can be formed on different substrates by a doctor blading method with a surfaee roughness rms around 6 nm. The WO3 NPs HTL was treated by a temperature annealing process at 80 °C for 5 minutes and provided a work ftmction of 5.35 eV. As shown in Figure 7.20, OSCs using WO3 NPs as HTL can provide comparable performance for both the normal and inverted device architectures. 

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