Overnight weekend shift woes?

I work friday and saturday overnight shift. I have to stay awake and I dont really have trouble with it, but I cant stay motiviated or get any work done. It not exactly a fast past job most of the time but I have many things I have to do. I feel like a slac off. NO one else is here so I end up not doing much. People have complaned things are not complete. I Have always been a very diligent and dedicated employee in other jobs. What do I do? I cant work any other times or change my hours. How do I stop being so lazy?