Hi,
I understand that you would like to plot a graph with exponential values equally spaced on the y-axis. Kindly refer to the linked documentation for the function semilogy which creates plots with a base-10 logarithmic scale on the y-axis, that is, the y axis has exponential values equally spaced.
To create plots with other logarithmic scales, the following answer describes an approach: https://in.mathworks.com/matlabcentral/answers/99020-is-it-possible-to-produce-a-plot-in-matlab-with-the-axes-scaled-based-upon-the-natural-logarithm