nuclear power is the result of breaking the bonds within the nucleus, bonds much stronger than the chemical bonds between atoms, with much more energy, and releasing that energy into heat. but your idea is already the most common form of energy production, burning shit! this is a process of breaking and reforming chemical bonds to release energy. there are other chemical reactions which could be used, but oxidation (burning) is the most cost efficient.

The hydrogen used in combustion systems does not exist abundantly in free form, but must be manufactured.

The unlikely collision of neutrons and the hydrogen molecule (bcause of relative size) will not produce significant amounets of energy, nor additional neutrons to sustain or increase power generation levels, which is the whole point.