Can Dutch citizens can get a toursit visa for the mainland of China on arrival in Hong Kong? thanks

I'm from the Netherlands and i will go backpacking in China together with my mother. We will arrive in and depart from Hong Kong. For our traveling we want to go to the mainland of China. I obtained information that says that for Hong Kong we don't need a visa. We do need for the mainland; in this case a single entry visum. Now would we like to apply for the visa in Hong Kong. Is that possible? Or is it better to arrange visa in the Netherlands before departure?

Thank you!