Do you intend to charge a battery? That's a consideration since you don't want current to flow backwards at any time.
Do you intend to have 2 transistors... one conducting while the other is Off? They must be oriented so current always goes through the inductor in one direction.
They must be biased accordingly.
To gain efficient utilization of the solar panel, you shall draw continual smooth current at maximum power it can produce. You may find the easiest method to achieve this is by interleaving two or more converters.