First of all, I am still new to software development. I am starting to developing a social network website as a project for a project. I am going to use PHP, PDO, MYSQL, Javascript, CSS etc for the development. In fact, those are the ones I have known already. I have discussed with my supervisor and he is not okay developing the site with these. I ask for alternatives but I think he just thinks that PHP is not powerful and not well performed enough. Is it true? Is PHP is a bad choice for developing such a site like a facebook? also, I have read online that PHP is vulnerable to SQL injections etc. so it got me into thinking maybe PHP is a bad choice at all.

BTW I can not use Social network Development Platforms Such as Social Engine, OXwall etc.

So can anyone answer me how to develop such a site without PHP? I do not know nodejs, angularjs etc. why should I use them so any help?