Question

THE CURRENT IN THE FORWARD BIAS IS KNOWN TO BE MORE THAN CURRENT IN REVERSE BIAS .WHAT IS THE REASON TO OPERATE THE PHOTODIODE IN REVERSE BIAS

Answer 1

Current in forward bias diode is more due to forward current than reverse saturation current. You are right.

Solar cell is sun(photonic) device. It receives energy from the sun to operate.

A wide range of sunlight is absorbed in reverse bias, as solar cell is operated in reverse bias.

Also, reverse bias produces strong electric field in the depletion region which is used to separate generated e-h pair due to sunlight.

These are two reason behind the operation of solar cell in reverse bias.