Surface morphology, film property

Morphology, surface (film growth) The physical properties of a surface such as roughness, porosity, long- and short-range features, etc. that can be seen using an optical microscope, a scanning electron microscope (SEM), or an atomic force microscope (AFM). 

Saha et al. [109] have proposed an improved ion deposition methodology based on a dual ion-beam assisted deposition (dual IBAD) method. Dual IBAD combines physical vapor deposition (PVD) with ion-beam bombardment. The unique feature of dual IBAD is that the ion bombardment can impart substantial energy to the coating and coating/substrate interface, which could be employed to control film properties such as uniformity, density, and morphology. Using the dual lABD method, an ultralow, pure Ft-based catalyst layer (0.04-0.12 mg Ft/cm ) can be prepared on the surface of a GDL substrate, with film thicknesses in the range of 250-750 A. The main drawback is that the fuel cell performance of such a CL is much lower than that of conventional ink-based catalyst layers. Further improvement... 

Basic issues such as surface reactions, surface film formation, passivation, ionic and electronic transport phenomena through surface films, problems in uniformity of deposition and dissolution processes, correlation between surface chemistry, morphology, and electrochemical properties are common to all active metal electrodes in nonaqueous solutions and are dealt with thoroughly in this chapter. It is believed that many conclusions related to Li, Mg, Ca, and A1 electrodes can be extended to other active metal electrodes as well. 

In conclusion, the doping of oxide materials opens promising new routes to change the morphology and electronic properties of supported metal particles as used in heterogeneous catalysis. Thin oxide films are ideally suited to elucidate such doping effects, as they can be explored by means of conventional surface science techniques at a fundamental level. The identified mechanisms can be transferred to real catalysts later, as the doping approach is not based on specific thin-film effects. 

The quality of the results from SEC-FTIR strongly depend on the surface quality of the deposited sample fractions. Cheung et al. demonstrated that the surface wetting properties of the substrate dominate the deposit morphology [145]. The spectra fidelity, film quality, resolution and polymer recovery were considered by Balke et al. [ 146]. For different interface designs it was found that the morphology of the deposited polymer film was a key parameter for quantitative measurements. 

One study in our laboratories investigated the direct link between PPy film morphology and mechanical properties.126 Observation of the fracture surfaces of the films showed a roughened surface with cone-shaped features (Figure 3.9), similar to those observed in transmission electron microscope (TEM) micrographs of the film cross sections (described earlier). It was concluded from this study that the cone boundaries are points of weakness within the film that allow easier crack propagation. Thus, films with less prominent boundaries should show improved fracture resistance. 

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