The font changing for the whole document generated by LaTeX could be done by specifying the following line in the LaTeX preamble:
If the source LaTeX document is genereted by Sphinx you should add the line in the end of the "latex_preamble" in the config.py.
\renewcommand{\rmdefault}{cmss}
from here
If you want to use non-default font, you should to install the corresponding package first. The "winfonts" package contains the following fonts:
Arial Franklin Gothic Tahoma Comic Sans
Georgia TimesCourier New Palatino Linotype Verdana
You can download it from here:
Now you can use a non-default font for the pdf:
\renewcommand{\rmdefault}{verdana}