List of lists elementwise greater/smaller than
Boole@Positive[a-b]
{{0, 1, 0}, {1, 0, 1}, {0, 1, 0}}
1-UnitStep[b-a]
{{0, 1, 0}, {1, 0, 1}, {0, 1, 0}}
kglr took the fast, vectorized operations. Here are some less optimal ones that you can have a look at for fun or for learning:
Boole@MapThread[Greater, {a, b}, 2]
{{0, 1, 0}, {1, 0, 1}, {0, 1, 0}}
Boole@Apply[Greater, Transpose[{a, b}, {3, 2, 1}], {2}]
{{0, 1, 0}, {1, 0, 1}, {0, 1, 0}}