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Perovskite solar cells have been rapidly developed in the past ten years. It was demonstrated that the interfacial layer plays an important role in device performance of perovskite solar cells. In this study, we report utilization of a photoinitiation-crosslinked zwitterionic polymer, namely dextran with carboxybetaine modified by methacrylate (Dex-CB-MA), as an interfacial layer to improve the film morphology of the CH 3 NH 3 PbI 3 photoactive layer and the interfacial contact between the poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) hole extraction layer and CH 3 NH 3 PbI 3 photoactive layer. It is found that the Dex-CB-MA thin layer forms a better band alignment between the PEDOT:PSS hole extraction layer and CH 3 NH 3 PbI 3 photoactive layer, and improves the crystallization of the CH 3 NH 3 PbI 3 photoactive layer, resulting in efficient charge carrier transport. As a result, perovskite solar cells with the PEDOT:PSS/Dex-CB-MA hole extraction layer exhibit more than 30% enhancement in efficiency and dramatically boosted stability as compared with that with the PEDOT:PSS hole extraction layer. Our studies provide an effective and facile way to fabricate stable perovskite solar cells with high power conversion efficiency.
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Utilizing Toray Paper as a Metal‐Free, High Surface Area Electrode for Photosystem I–Driven Mediated Electron Transfer
One challenge in capitalizing on the affordability, sustainability, and accessibility of biohybrid solar energy conversion, including devices based on Photosystem I (PSI), is the identification of metal‐free electrode materials to replace the inorganic substrates commonly found in solar cell development. Herein, commercially available Toray carbon paper (CP) is investigated as a high surface area, carbon electrode for the development of photoactive bioelectrodes consisting of PSI and poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). Mediated anodic photocurrent is achieved at both PSI multilayer and PSI–polymer composite films on CP electrodes subjected to flame pretreatment. Film preparation is optimized by utilizing potential sweep voltammetry in place of potentiostatic conditions for polymerization. The optimized PSI–PEDOT:PSS films achieve a threefold increase in polymer growth under potential sweep conditions, quantified through net charge consumed during electropolymerization, resulting in a fourfold increase in photocurrent density (−53 vs −196 nA cm−2). The ability to prepare photoactive PSI‐polymer films on metal‐free CP electrodes opens the door to a rapidly scalable system for biohybrid energy production ultimately leading to more affordable, sustainable, and accessible energy.
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- Award ID(s):
- 1852157
- PAR ID:
- 10393586
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Energy Technology
- Volume:
- 11
- Issue:
- 4
- ISSN:
- 2194-4288
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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