I am wondering, is there any way to create an input in format "DD/MM"?

I tried this, but knew it shouldn't work:

var question5  = "<div id='2'><p>Start of the fiscal year</p><br>" 
                   + "<input type=\"date\" id=\'startdate\' placeholder=\"dd/mm\"></input><br></div>";

I am adding the element using document.getElementById("ID").innerHTML += question.

Could you, please, help me with it?