Revealing the electronic structure, heterojunction band offset and alignment of Cu₂ZnGeSe₄: a combined experimental and computational study towards photovoltaic applications

Abstract

Cu2ZnGeSe4 (CZGSe) is a promising earth-abundant and non-toxic semiconductor material for large-scale thin-film solar cell applications. Herein, we have employed a joint computational and experimental approach to characterize and assess...

GeSe-evoked synchronous strategy for electrodeposited CZGSe solar cells

“…Three major peaks were observed in both samples and were assigned to the kesterite phase, indicating a single pure structure. 21,24 Noticeably, two other peaks were present in the CZGSe-B sample, belonging to MoSe 2 , consistent with the observation of the morphological results. The Raman spectra for both were also recorded, as shown in Fig.…”

“…Furthermore, Ge is generally introduced by thermal evaporation, magnetron sputtering, or an organic solvent-based solution process, but with high-standard equipment and under rigorous conditions. [21][22][23][24] Thus, new synthetic technology for Ge incorporation into an electrodeposited prefabricated layer, which possesses the capacity for low-demanding equipment and high safety factors was proposed in this work.…”

“…Several strategies have been produced to address this, such as vacuum-based magnetron sputtering/electron beam evaporation and organic solvents-based solution process. 15,[19][20][21][22][23][24] However, these strategies generally involve high costs, less security, and/or intricate deposition technologies. Thus, to explore low-cost, green, and simple new synthesis technology, optimizing the appropriate absorber conditions and purifying the phase impurities are the most important priorities at present.…”

Further Boosting Solar Cell Performance via Bandgap-Graded Ag Doping in Cu2ZnSn(S,Se)4 Solar Cells Compared to Uniform Ag Doping

“…Among the substitutes to traditional energy, economic and environmental-friendly solar energy has the most extensive development prospect because of its great potential in meeting the supply of large-scale low-carbon electricity in the future. − In the numerous photovoltaic (PV) devices, crystalline silicon (c-Si), which occupies a very important position in the PV field, is gradually being replaced by metal chalcogenide-based thin-film PV technology due to c-Si’s high processing cost and complex manufacturing process . Among the different chalcogenide PV devices, only Cu­(In,Ga)­Se 2 (CIGSe) and CdTe devices have met efficiency requirements for commercial production. − However, the disadvantages of In, Ga, Te, and Cd, such as toxic properties, high cost, and shortage of element reserves, limit their large-scale development. , Cu 2 ZnSn­(S,Se) 4 (CZTSSe) is a derivative of commercialized CIGSe devices with similar structure and optoelectronic properties, which is rich in earth resources, low in production cost, and friendly for environmental protection. − Furthermore, the theoretical Shockley–Queisser limits for CZTS, CZTSe, and CZTSSe solar cells are 32.4, 31.6, and 31.0%, respectively, which are higher than that for CIGSe of 31.0%. − Due to the similar properties, the development experience of CIGSe solar cells can provide great technical support for CZTSSe solar cells . Thus, CZTSSe is considered as an absorber layer material with bright prospect in the field of PV devices.…”

Analysis of Loss Mechanisms in CZGSe Thin-Film Kesterite Solar Cells: A Statistical Distribution for Defects and Traps

“…Normally, the bandgap of the kesterite absorber layer can be adjusted by changing the S/Se concentration or by placing the tin (Sn + ) molecules with silicon (Si + ) or germanium (Ge + ) [17][18][19][20]. It is investigated that Cu 2 ZnGeSe 4 (CZGSe) seems to be quaternary semi-conductor material groupings I 2 -II-IV-VI 4 which has been experimentally and theoretically demonstrated to be p-type semiconductors with a direct bandgap of 1.4eV and extremely high rate of photon energy absorption coefficient similar to CIGS and CZTS materials [16,17,21]. CZGSe forms a tetragonal crystallographic orientation with 2 no.…”