Nonchemistry person here. Why can't we create a catalyst

Hydroelectrolysis aren't the only reason hydrogen fuel isn't being used right now. There are other issues like transportation and hydrogen gas being a gas with low density so you have to use <extremely> high pressures and <extremely> low temperatures to make transporting it in a car or other vehicle feasible. I have heard other ideas such as absorbing the H2 into a metal block or some other shit but that's besides the point. Also, another possibility if H2 is used as fuel is that new kinds of accidents will happen, so, for example, Hollywood style car explosions actually can happen with hydrogen-fuel cars (I have no proof of this but the gist is that terrorists can use the cars to drive into walls and blow them up).

But the reason a catalyst actually matters is because of a thing called overpotential and efficiency in electrolysis. There is also a thing called Hess's law which means that in order to turn H2O into H2 and O2 you have to put the same amount of energy into the water as would be released by burning the H2 in oxygen. Together these things mean that in the electrolysis process an incredible amount of energy is expended and a catalyst will definitely be used to make the process as efficient as possible. By using a good catalyst I'm sure you can save a shitton of energy.

However, you seem to be confused about catalysts. They CANNOT make energy, only make the process more efficient. The maximum efficiency of any process is 100%. Basically you have to "unburn" the water, and that takes, at a minimum, the exact same energy burning the hydrogen gave. But you will probably use up more than you will get when you burn the hydrogen you get as fuel, and you use a catalyst to reduce this additional energy cost. This inefficiency is also a major reason this isn't used. And since the energy to get the H2 is likely provided by burning fossil fuels, it is easier to just skip the middleman and use petrol.

>>8938330
Because we don't fully understand what causes catalysis. We don't know what catalizes thst particular reaction. As it stands, the voltage requirement for electrolysis of water isn't incredibly high. A bigger problem is that Hydrogen is not our best rocket fuel

>>8938473
https://www6.slac.stanford.edu/news/2016-03-24-new-catalyst-three-times-better-splitting-water.aspx

>>8938473
Sometimes I fully don't understand your mom at night.

>>8938330
Because catalysts don't (directly) increase efficiency, only rates.

>>8938472
So you're saying that even if we created an amazing catalyst, the required input energy would always exceed the output energy?

>>8939795
not that anon, but with pretty much any chemical reaction, you can never get 100% yield. it's why it is better to just use something else that is already been made (fossil fuel in this case) and using that.

>>8938472

I thought catalysts wouldn't change the energy inputs or outputs of a reaction, only make it happen much faster by reducing activation energy.

>>8939826
>I thought catalysts wouldn't change the energy input of a reaction
>but I think the activation energy is lower

are you okay m8
that's some serious dissonance

>>8939847

Do you understand what activation energy is? Hint, it has nothing to do with enthalpy. Energetics 101.

File: save_car.jpg (66KB, 468x283px) Image search: [Google]

66KB, 468x283px

>>8938472
>> hollywood style car explosions
No. Volumetric energy density is a big issue though, but with modest improvements to fuel cell efficiency and hydrogen storage technology, we can have fuel cell cars with the same range as gasoline vehicles. There is even the possibility of having greater range. Most of the gains here come from the more efficient conversion of chemical energy to mechanical work

>>8939871
>pic
That seems like a very idealistic failure mode in a car crash. Although truly enough it's true the fact that it's a gas might make it easier to vent it away than say leaking gasoline. I reserve my doubts about just how well you'll do that when your car is turned into a dumb wreck of metal and plastic.

>>8938330
No superAI yet

Does anyone know the oxidation steps when
C2H4 -> CH20

I know its similar to the methane steps, but not sure how it goes when I´ve got two carbons..

>>8941202
>CH20
... I maybe be but a simple country chemist, but that doesn't sound right.

>>8939906
Hydrogen doesn't pool on the ground like gas does. It can't explode because there's no oxygen in the tank

>>8939850
Kinetics haha

>>8938472
Just like to add that, since hydrogen gas is clean, it will be good to have hydrogen powered cars in cities, where the air in some are getting really bad.
Even tho the gas is made with fossile fuel.