Why cant a current be produced by a photovoltaic cell?

Question

The intensity of EMR in a spectrum of light was measured by a photovoltaic cell. The photovoltaic cell was not only moved within the visible spectrum but also in teh dark region just byond the visible spectrum's red end. The photovoltaic cell produced a current even in this dark region.

Why cant a current be produced by a photovoltaic cell while it was in the dark region next to the red light?

Answer 1

There's no reason to expect the photovoltaic process to have the same spectral sensitivity as the human eye.  'dark' is relative to human vision.

Answer 2

You have discovered infrared light.