A tenth of five percent is just about 5 Watts per square meter in direct sunlight.
Realistically speaking, the overall collection efficacy would be on the order of half a watt per square meter, which means the manufacturing costs of such window panes would be far greater than their lifetime energy production.
Since the material costs are negligible it's 'only' a matter of finding a convenient manufacturing process that integrates well with the current one for glass panes (or a simple application in post).
This is a very stable chemical in its crystal form, immune to both acid and base, which is good for a solar cell material. However, you have to make this stuff at high temperature and pressure, which is time-consuming and expensive. Not to mention that high temperature and pressure might be a non-starter for applying it to a lot of the materials you'd like to place it on, such as the safety glass used in commercial buildings (I don't know if that would work or not, but it's something they'll have to deal with).
Another thing to think about with any potential new material is toxicity. Selenium is poisonous, especially vaporized or powdered, so you wouldn't want this stuff flaking off windows and getting into the air in a city. You'd also have to make sure it isn't going to kill people if there's a fire or short circuit in the panel.
Jeffhans1
Mar 9, 2014