Can the incident photo-to-electron conversion efficiency be used to calculate short-circuit current density of dye-sensitized solar cells

The relationship between the integration of the incident photo-to-electron conversion efficiency (IPCE) and the measured short-circuit current density (JSC) of dye-sensitized solar cell (DSC) has been analyzed. The JSC of DSC under full sun is usually considered to be determined by the overlap between its spectral IPCE and the spectral photon flux incident on the cell. However, the IPCE spectrum has been found to be influenced by the bias light intensity in many practical cases. Through theoretical deduction, we have proved that JSC calculated from IPCE spectrum is related to the slope at corresponding incident light intensity on the short-circuit photocurrent density–incident light intensity (JSC−Elight) curve. The equal relation between JSC calculated from IPCE and JSC practically measured can only be obtained when the JSC−Elight curve is a straight line through the origin of the coordinates. The measured results of four DSC samples with different working condition show a good agreement with the theory. In addition, a simple method to validate the accuracy of IPCE measurement is also demonstrated.

► The theoretical relationship between Elight depended IPCE and JSC of solar cells.
► When JSC−Elight curve is nonlinearity, IPCE dependents on the bias light intensity.
► Experimental results of DSC samples confirmed the theoretical derivation.
► A simple method was used to verify the accuracy of IPCE measurement.