If your are looking for a genuine free web hosting plan for your PHP / MYSQL site with reasonable web space and features, then you don't have to search anymore. Out of many free web hosting sites available online, biz.nf seems to be the best of the lot as far as providing free web hosting with basic necessary configuration and no advertisement is concerned.
They do have Personal and Business plans where they charge monthly fees for extra facilities but the configuration offered under free plan is more than enough for a website which is small and doesen't require lot of bandwidth and space.
Under free plan the hosted website will get a subdomain (.co.nf), 250 MB disk space, 5GB of data transfer, 1 email account, 1 MYSQL database with 10 MB size with phpMyadmin support and 1 FTP account. This configuration seems good enough for a static website with few information pages and couple of form pages to collect user data. But if the website is going to expand and grow in future then no free plan is advisable. There are reasonable paid hosting plans available at GoDaddy, Hostgator etc which can cater to the large space and bandwidth demand of a website.
To know more about what's included and what's not in the free hosting plan of biz.nf check out their hosting details page: Free web hosting without ads