Photoconductivity of Selenium
A very handy diagram and explanation of photoconductivity is shown below, from the American Physical Society page Viewpoint: Holey Intrinsic Photoconductivity:



The caption explains:


  Excitation process leading to photoconductivity in a condensed matter system (upper panel) and its cold-atom counterpart (lower panel). In the condensed matter system, incoming laser light ($hv$) excites an electron to the valence band, leaving a positively charged hole behind. In the cold-atom analogy, the optical lattice is tuned to allow an atom to move into the excited band, also leaving a hole behind. 


From the Wikipedia page Photoconductivity, states that some 'classic' examples of photoconductive materials (asides from selenium) include:


The polymer polyvinylcarbazole
Lead sulfide


Some more examples exist in the paper Organic photoconductive materials: recent trends and developments include the chemical classes:


Phthalocyanines
Squaraines
Azo pigments
Perylene pigments