Problems on switching MOSFET for boost converter
Vgs(th) it's just to start driving, to really serve as a switch you need VGS = 4.5 V (see rds(on))
You must try other circuits as follow
boost converter 1.5 volts input 5 volts output 200 mA,
boost converter 1.5 volts input 5 volts output  10 mA,
boost converter 1.5 volts input 5 volts output 500 mA,
boost converter 1.5 volts input 5 volts output 300 mA