Simply stated. Structure (chemical structure) is given by atom arrangement and connectivity (single, double bonds, rings, aromaticity etc.) and it is something like "very detailed view to some matter". The same chemical structure can result in different morphology (which can be, for example, envolved by non-bonding interactions - e.g. pi-pi interactions) which can be based on the way of material isolation or preparation (crystallization, evaporation, vapor deposition). Morphology is not so detailed view to the matter. In the case of graphene is this problem less obvious since graphene is theoretically a single infinite layer so there is no space for something like morphology (if we will not take account some wrinkled layer or folded one). In reality most of materials named "graphene" are, strictly speaking, not graphene but partially reduced grapheneoxide. Some graphenes are not formed by one layer only. The size and shape of graphene sheet can differ and can play role too. Moreover, there are still a lot of oxygen and hydrogen atoms in case of chemicaly reduced grapheneoxide, which have significant contribution to the existence of plenty non-bonding interactions posibilities. There is one link, which can demonstrate the influence of drying method to morphology of graphene.

http://pubs.rsc.org/en/content/articlelanding/2016/ra/c5ra23123j#!divAbstract

Thank you sir Lukáš Richtera