I also want to add some limitations of LI fi here:
The main problem is that light can’t pass through objects, so if the receiver is inadvertently blocked in any way, then the signal will immediately cut out. ―If the light signal is blocked, or when you need to use your device to send information — you can seamlessly switch back over to radio waves. Reliability and network coverage are the major issues to be considered by the companies while providing VLC services. Interference from external light sources like sun light, normal bulbs; and opaque materials in the path of transmission will cause interruption in the communication. High installation cost of the VLC systems can be complemented by large-scale implementation of VLC though Adopting VLC technology will reduce further operating costs like electricity charges, maintenance charges etc. This research report categorizes the global VLC technology market; based on component, applications, and geography. Li-Fi uses light-emitting diodes (LEDs) which are rapidly gaining in popularity for standard light bulbs and other domestic and commercial purposes. They are expected to be ubiquitous in 20 years. VLC is not
in competition with Wi-Fi, Prof. Haas says, it is a complimentary technology that should eventually help free up much needed space within the radio wave spectrum.
Hope this will help. You may refer to these links for further study
http://www.ijarcsse.com/docs/papers/Volume_3/11_November2013/V3I11-0434.pdf
http://www.ermt.net/docs/papers/Volume_3/3_March2014/V3N3-181.pdf
https://www.google.co.in/urlsa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0ahUKEwi4qcL3x8fNAhXKpJQKHTsmDGYQFggsMAI&url=http%3A%2F%2Fwww.indiamart.com%2Flifpublications%2Faboutus.html&usg=AFQjCNGW-hHJ1zlG4ZN9dbImv_4RjQhmyw&bvm=bv.125596728,d.dGo
Thanks