====== Metallic catalysts ======

The history of using metallic catalysts to speed up chemical reactions goes back to the mid 1800s. They typically make reaction rates many thousands of times faster.

Without metallic catalysts, many current-day commercial reaction processes would be impractically slow.

An important factor in the catalytic process is that the catalyst itself is// not changed// during the reaction. It's also known that increasing the surface area of the catalyst can make a dramatic difference to the reaction speed. Leading to the conclusion that electrochemical  / quantum effects must be happening directly at the metallic surface boundary.

The mechanisms at work in the metallic catalyst process have been extensively studied, and there are many models offering partial explanations. (example, see [[https://en.wikipedia.org/wiki/Catalytic_cycle|Wikipedia]]).

But a clear, universal, agreed-upon explanation of the processes involved - at an atomic / quantum level - has not yet been found.

>A good knowledge of the physico-chemical processes taking place on metal surfaces during catalytic reactions is highly desirable for many technological applications, but still far from being attainable in many cases. __Even simple and paradigmatic cases are, unfortunately, not fully understood.__\\  \\ Source : [[http://www.phantomsnet.net/files/abstracts/TNT2005/TNT05_RodriguezOscar.pdf|Fritz-Haber-Institut der MPG]]

>If we want to go beyond the study of particular cases, we should work to establish a unified theory that will envelop and explain all of the cases in metal catalysis, regardless if that is based on homogeneous or heterogeneous chemical, photochemical, electrochemical, or photoelectrochemical catalysts. At the end, all of them are based on electronic interactions, and, to achieve global explanations, we can make use of the knowledge generated by the physicists and chemists on solid-state chemistry, physical chemistry of surface, and chemical reactivity.
>\\ Source : [[https://pubs.acs.org/doi/10.1021/acs.chemrev.7b00776#|Chemical Reviews, 2018, 118, 10, 4981–5079]] {{:oa_padlock_grn.png?16&nolink|Open Access}}

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For a specific example, see [[content:chemistry:gold_catalysis]]

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