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The problem with electrolytic hydrogen is that electricity is expensive, not that the process is inefficient.
Well more accurately, it is both expensive and inefficient. The best catalysts (the ones which operate at the lowest overpotential) are often expensive iridium oxides. Catalysts made from more abundant elements tend to require a higher applied voltage, which reduces the efficiency of the system. That said, if you're burning natural gas to make electricity to split hydrogen from water, you're much better off steam reforming the methane directly to hydrogen in terms of efficiency.