Catalytic materials prepared by chemical vapor deposition

Abstract

In the 1980`s appeared the first several scientific papers dealing with chemical vapor deposition (CVD) of nanostructured catalytic materials. Since then, the tremendous increase in the number of related publications indicates the significant importance of CVD for the preparation of catalysts. CVD has the capability to generate various types of catalytically attractive nano-scale structures by modifying the surface properties of massive or even nanodivided substrates. Relatively new CVD processes such as catalytic CVD, fluidized-bed CVD, rotary CVD, two-step CVD and large spot laser CVD allow the formation of nanoparticles, nanotubes, nanofibers, nanocomposites and porous or oriented films. Intensive research is being performed on the production of CNTs and the preparation of supported catalysts by CVD. This paper provides an overview of the relatively new CVD processes involved in the preparation of catalytic materials and some representative examples reported in the open literature.

Effect of Intrinsic Properties of Anions on the Electrocatalytic Activity of NiCo2O4 and NiCo2OxS4–x Grown by Chemical Bath Deposition

“…However, these methods are quite tedious and difficult to control. 24,25 Alternatively, a thin layer of catalyst materials can also be directly grown on substrates using hydrothermal reactors by appropriate tuning of synthetic conditions. [14][15][16][17]26,27 However, it has been noticed that although the same reaction conditions are used, minor differences in hydrothermal setup across labs often lead to the formation of different materials.…”

“…Techniques such as chemical vapor deposition or physical vapor deposition are generally employed to directly deposit catalyst layers onto conductive substrates during catalyst synthesis. However, these methods are quite tedious and difficult to control. , Alternatively, a thin layer of catalyst materials can also be directly grown on substrates using hydrothermal reactors by appropriate tuning of synthetic conditions. − ,, However, it has been noticed that although the same reaction conditions are used, minor differences in hydrothermal setup across labs often lead to the formation of different materials. This motivated us to develop a more general method that will use relatively cheap and easily available equipment and is able to produce robust thin layers on substrates.…”

Single-step co-deposition of nanostructured tungsten oxide supported gold nanoparticles using a gold–phosphine cluster complex as the gold precursor

“…the CVD deposited gold-NP (either supported or ‘bare’) were an order of magnitude more active than gold-NP deposited from the same precursor via a solution phase method. It has been found previously that higher catalytic performance is observed in CVD deposited materials than those produced using solution-phase methods [24], although it should also be noted that the particle sizes (up to 50 nm) for the solution phase gold-NP were considerably larger than those for CVD deposited gold-NP (16 nm) or tungsten oxide supported gold-NP (∼6 nm).…”