Nanoparticle-based contacts to CdTe

摘要

Our team has been investigating the use of particle-based contacts in CdTe solar cell technologies. Toward this end, particles of Cu-doped HgTe (Hg-Cu-Te) and Sb-Te have been applied as contacts to CdTe/CdS/SnO_2 heterostructures. These metal telluride materials were characterized by standard methods. Hg-Cu-Te particles in graphite electrodag contacts produced CdTe solar cells with efficiencies above 12percent and series resistance (R_(se)) of 6 #OMEGA# or less. Metathesis preparation of Cu(I) and Cu(II) tellurides (i.e., Cu_2Te and CuTe, respectively) were attempted as a means of characterizing the valence state of Cu in the Hg-Cu-Te ink. For Sb-Te contacts to CdTe, open circuit voltages (V_(ocS)) in excess of 800 mV were observed, however, efficiencies were limited to 9percent; perhaps a consequence of the marked increase in the R_(se) (i.e., >20 #OMEGA#) in these non-graphite containing contacts. Acetylene black was mixed into the methanolic Sb-Te colloid as a means of reducing R_(se), however, no improvement in device properties was observed.