Formation of BaSi2 heterojunction solar cells using transparent MoO<i>x</i> hole transport layers

Abstract

Heterojunction solar cells that consist of 15 nm thick molybdenum trioxide (MoOx, x &amp;lt; 3) as a hole transport layer and 600 nm thick unpassivated or passivated n-BaSi2 layers were demonstrated. Rectifying current-voltage characteristics were observed when the surface of BaSi2 was exposed to air. When the exposure time was decreased to 1 min, an open circuit voltage of 200 mV and a short circuit current density of 0.5 mA/cm2 were obtained under AM1.5 illumination. The photocurrent density under a reverse bias voltage of −1 V reached 25 mA/cm2, which demonstrates the significant potential of BaSi2 for solar cell applications.