COPPER BASED CHALCOGENIDES
This area of research focuses on two chalcogenide materials, CZTS and CIGS, which are employed as the absorber layer in solar cells. These thin-film semi-conductors are far less material intense than current silicon based solar modules. They are almost identical in crystal structure, with the expensive rare earths indium and gallium in CIGS being replaced with cheap and abundant zinc and tin in CZTS. CIGS has achieved power conversion efficiencies (PCE) above 20% and as such, is already being procduced on an industrial scale. However, its wide-spread adoption is limited by the scarcity of its constituent elements. CZTS does not possess these problems, and is therefore being touted as the material of choice for the next generation of thin-film PV technology. Our team holds several world records for the PCE of CZTS solar cells, and one of our main research goals is to elevate it to a level where CZTS can become a commercially viable product. Our main research goals in this particular field are developing wide band gap CZTS for tandem silicon devices, selenium doped CZTS for single junction devices and CIGS based thin-film devices.
RESEARCH GALLERY
 CZTS solar cells with over 10% power conversion efficiency enabled by heterojunction heat treatment |  Recombination analysis in heat treated heterojunction CZTS solar cell |  TEM, HAADF images and intensity profile of heat treated CZTS |
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 Band alignment study for heat treated CZTS |  SEM image and Auger profile CZTSSe deivce |  TEM image CZTS device fabricated by the sol–gel method and EDS mappings for different compositional |
 Stable chemical potential regions for CZTS (left) and CZTSe (right) |  Study of Germanium doped CZTS solar cells |  2D topography and surface spatial maps of kesterite compounds |
 Over 9% Efficient Kesterite CZTS Solar Cell Fabricated by Using ZnCdS Buffer Layer |  HADDF images and corresponding EDS elemental line scan of 9% efficient CZTS device |  EDS mapping of CZTS devices with differing buffer layers |
 XPS composition profile, VB data, band bending and band alignment schematic of p-n junction with ZnC |  J-V characteristiscs of CZTS cell with ZnCdS buffer layer |  SEM images for two CZTS thin film devices produced via sol-gel solution |
 Raman Spectroscopy of sol-gel CZTS samples |