The shining of the moon at night is the reflection of the sun bouncing off the surface of the moon. That is why we on Earth can see the moon appear as shining.
For me:
At day time when the sun heats the moon, the moon become hot by the energy absorbed and for anything that is hot it radiates light to some extent somehow our eyes can only receive light for wave length about 400 nm to 700 nm, and that light radiated from moon has low intensity from light radiated from the sun, we cannot see moon light at day time. At night, we can easily see the moon light since no longer exist light from the sun. Therefor, anything when it is being heated, it radiates light eventually. And for this, certainly, we can store the sun light at day time and use it at the night time, don't you think so?