Dear Liana,

There is always confusion for defining onset potential. This confusion rises due to gradual increase in photocurrent from faradaic to non-faradaic region. The most appropriate way of determining onset potential is to draw tangents in non-faradaic zone (conventionally horizontal line) and faradaic zone in LSV curve. Abscissa  of point where these two tangents intersect, gives the onset value.

Hi,

There are three common ways to define onset potential.  The potential at the intersection point of the tangent at maximum slope of photocurrent and the dark current curve is considered as onset potential and this is the common way many people have reported.The potential at which the photocurrent exceeds a certain defined value or the potential at which dj/dv exceeds a certain defined value are also considered as onset potential. However, it must be bear in mind that all these methods are somewhat arbitrary and may be more or less appropriate depending on the shape of the J-V curves at hand. 

Andebet Gedamu

Hi,

Can you please provide a reference that describes the onset calculation based on a particular dj/dv

Thank you for the information.

Dear RG members, do we need a certain reference current to get the onset potential if not we will get different onset potential for a particular LSV plot so what will be our reference point?