Jo, H. Kim, J.K. Kim, J. Seong, T.-Y. Son, H.J. Jeong, J.-H. Yu, H. 2024-01-19T13:03:00Z 2024-01-19T13:03:00Z 2022-01-28 2021-12-27 2574-0962 https://pubs.kist.re.kr/handle/201004/115929 Due to the excitonic nature, colloidal PbS quantum-dot solar cells have suffered from lower photocurrent densities than expected from the absorber band gap. The heterojunction between solution-processed ZnO and PbS quantum-dots has been predominantly explored for photovoltaic applications. However, the deeper conduction band minimum of typical PbS quantum-dots than that of solution-processed ZnO imposes a high electron barrier, limiting the short-circuit current densities of the resulting solar cells mostly below 30 mA/cm2. Here, we report that atomic layer deposition (ALD) of ZnO buffer at a low temperature can favor the interfacial band alignment and boost the photocurrent density over 35 mA/cm2 at PbS quantum-dot band gap of 1.18 eV. From our band structure analysis, the electron barrier with ALD-ZnO can be 0.55 eV lower compared to that with sol-gel ZnO. Furthermore, photoactivation of shallow gap states formed by hydroxyl species in ALD-ZnO induces band bending and efficient electron tunneling from PbS to ZnO. Due to the improved band alignment, the device with ALD-ZnO exhibits a significantly enhanced lifetime compared to that with sol-gel ZnO upon constant illumination at 1-sun. ？ 2021 American Chemical Society. English American Chemical Society Unprecedentedly Large Photocurrents in Colloidal PbS Quantum-Dot Solar Cells Enabled by Atomic Layer Deposition of Zinc Oxide Electron Buffer Layer Article 10.1021/acsaem.1c02511 1 ACS Applied Energy Materials, v.4, no.12, pp.13776 - 13784 ACS Applied Energy Materials 4 12 13776 13784 scie scopus 000756324400044 2-s2.0-85120321586 Chemistry, Physical Energy & Fuels Materials Science, Multidisciplinary Chemistry Energy & Fuels Materials Science Article PHOTOVOLTAICS TEMPERATURE PERFORMANCE ZNO atomic layer deposition colloidal quantum dot photoactivation solar cell zinc oxide