He pioneered wireless transmission but that's a whole world away from harnessing lightening. Wireless transmission relies on the fact that magnetism induces current in wires without a direct connection, hence induction loops. How most " wave and open" door entry systems work. Tessla was the pioneer of many electrical things we take for granted and as such would have realised the futility of trying to capture lightening. I don't think any proper scientist has ever attempted to capture and store lightening, with the possible exception of the Doc in Back to the future!