Catalytic etching

Catalytic etching, 41 359, 383-384 definition, 41 360-361 in low earth orbit, 41 414—415 models, 41 359, 360-362 plasma etching, 41 407-414 thermally generated free radicals, 41 406-407... 

Metal oxides, 31 78-79, 89, 102, 123, 157-158, 191, 32 199-121 see also Amorphous metal oxides Sulfate-supported metal oxides specific oxides adsorbed oxygen on, 27 196-198 binary, surface acidity, 27 136-138 catalytic etching, 41 390-396 coordination number, 27 136 electrocatalysts, 40 127-128 Fe3(CO)i2 reaction with, 38 311-314 Lewis acid-treated, 37 169-170 multiply-valent metals, electrocatalytic oxidations, 40 154-157 superacids by, 37 201-204 surface acidity, methods for determining, 27 121... 

The above definitions are somewhat different from those given in earlier publications. In earlier studies, thermal etching has been defined to be etching that takes place in nonreactive or mildly reactive gases or under vacuum. Catalytic etching has been defined to be any etching process that takes place in... 

The above model of catalytic etching is not universally accepted. Several older mechanistic models exist. For example, it was suggested that localized temperature gradients, induced by surface reactions, might lead to uneven rates of diffusion or volatilization, and hence catalytic etching. 

Historically, catalytic etching has been a poorly understood phenomenon, and it has not always been clearly distinguished from thermal etching. Moreover, the largest number of studies have focused on platinum (3, 27, 34, 124-130) although the catalytic etching of silver (122, 131, 132), copper (16, 28, 133), nickel (134), and some platinum alloys (51, 121, 135-138) has also been investigated. 

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