There is this concept which is being watched (taken interest in) a lot according to the currently available insufficient and unperfected Ferguson you can simply attach a small solar panel like device to the charging port of your phone or any other device to provide charging to it by converting the light from the sun or even from common house light bulbs , however obviously these small attachable solar panel currently being sold on Amazon and other online shopping markets are not good , the best of these present now can give you maximum charging of 0.725 watts of charging
However, despite these factors this is most probably the future for our charging devices as in future we might see highly sufficient solar panel built in each of of our charging devices or other electronic devices however, as of now radio frequencies are 10 times more charging gaster than solar power but if these radio frequencies are released a lot they become very dangerous for human health , so in the end we will have to settle for solar energy is a source of wireless charging unless we find another way to pass by.