There are two different companies that use the “mi-Home” name: Energie (France) and Xioami (China).
Integration with Energie is quite complex, but can be done. Or you can just use IFTTT, as you mentioned.
Xioami Devices can be individually added but they are not strictly following the same zigbee profile that Smartthings uses (the company Says they are only intended for use with their own hub) so there are 3 potential issues:
they can be really fiddly to pair. Many people report having to try 10 or 12 times for each device
they don’t work well with most repeaters, which can cause them to drop from the network a lot. IKEA Tradfri pocket sockets seem to be the exception, and fortunately those are very inexpensive, £9.99 as of this writing. But getting your network backbone set up right can be, again, fiddly.
at any time SmartThings could push out a hub update which could break the integration because of idiosyncrasies on the Xioami side. This has happened 2 or 3 times in the last two years. If this does happen, you just have to hope things will be ok again in the next update.
There are still people using these because of the price, but be prepared for some tears.
Or you could get their Gateway and just use IFTTT, but as @MinerJason mentions below, that only exposes some features and you have to set up as a China location.
See the FAQ (the topic title is a clickable link)
Also, for the future, be aware that just being “zigbee” is not enough. See that FAQ:
