Two-dimensional (2D) ternary materials recently generated interest in optoelectronics and energy-related applications, alongside their binary counterparts. To date, only a few naturally occurring layered 2D ternary materials have been explored. The plethora of benefits owed to reduced dimensionality prompted exploration of expanding non-layered ternary chalcogenides into the 2D realm. This work presents a templating method that uses 2D transition metal dichalcogenides as initiators to be converted into the corresponding ternary chalcogenide upon addition of copper, via a solution-phase synthesis, conducted in high boiling point solvents. The process starts with preparation of VSe2nanosheets, which are next converted into Cu3VSe4sulvanite nanosheets (NSs) which retain the 2D geometry while presenting an X-ray diffraction pattern identical with the one for the bulk Cu3VSe4. Both the scanning electron microscopy and transmission microscopy electron microscopy show the presence of quasi-2D morphology. Recent studies of the sulfur-containing sulvanite Cu3VS4highlight the presence of an intermediate bandgap, associated with enhanced photovoltaic (PV) performance. The Cu3VSe4nanosheets reported herein exhibit multiple UV–Vis absorption peaks, related to the intermediate bandgaps similar to Cu3VS4and Cu3VSe4nanocrystals. To test the potential of Cu3VSe4NSs as an absorber for solar photovoltaic devices, Cu3VSe4NSs thin-films deposited on FTO were subjected to photoelectrochemical testing, showing p-type behavior and stable photocurrents of up to ~ 0.036 mA/cm2. The photocurrent shows a ninefold increase in comparison to reported performance of Cu3VSe4nanocrystals. This proves that quasi-2D sulvanite nanosheets are amenable to thin-film deposition and could show superior PV performance in comparison to nanocrystal thin-films. The obtained electrical impedance spectroscopy signal of the Cu3VSe4 NSs-FTO based electrochemical cell fits an equivalent circuit with the circuit elements of solution resistance (Rs), charge-transfer resistance (Rct), double-layer capacitance (Cdl), and Warburg impedance (W). The estimated charge transfer resistance value of 300 Ω cm2obtained from the Nyquist plot provides an insight into the rate of charge transfer on the electrode/electrolyte interface.
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.
- Award ID(s):
- 1852157
- NSF-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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