Magnetohydrodynamics, ionizing combustion exhaust then converting its kinetic energy to electricity

I am trying to understand how to make generation of electrical power more efficient by using Faraday's law to directly convert the kinetic energy of the ionized or easily ionizable exhaust gases of combustion (oxidation of hydrocarbons or to make things simpler just hydrogen) into electrical energy. In this system, the only real moving parts would be the motion of the ionized or plasma exhaust gas medium through the surrounding faraday coils. We may need a fan to coax the pre-combustion gases in a linear flow. The usable current would be induced in the Faraday coils from the accelerating or decelerating ionized gas from the exhaust.

My main question is how to completely ionize the exhaust gases at the point of combustion. My understanding is that these are already ionized at the instant of combustion but rapidly de-ionize when the oxidation reduction process is complete.

Hydrocarbon combustion does produce ions, due to chemiionization mechanisms. This does make flames more highly ionized than other gases at the same temperature. That having been said, the concentration of ions is still very small (rarely more than $10^{-6}$ by volume). You can augment this somewhat with metal salts but even that has limits. Approaching complete ionization is unlikely.