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Abstract Enzymatic Fisher‐Tropsch (FT) process catalyzed by vanadium (V)‐nitrogenase can convert carbon monoxide (CO) to longer‐chain hydrocarbons (>C2) under ambient conditions, although this process requires high‐cost reducing agent(s) and/or the ATP‐dependent reductase as electron and energy sources. Using visible light‐activated CdS@ZnS (CZS) core‐shell quantum dots (QDs) as alternative reducing equivalent for the catalytic component (VFe protein) of V‐nitrogenase, we first report a CZS : VFe biohybrid system that enables effective photo‐enzymatic C−C coupling reactions, hydrogenating CO into hydrocarbon fuels (up to C4) that can be hardly achieved with conventional inorganic photocatalysts. Surface ligand engineering optimizes molecular and opto‐electronic coupling between QDs and the VFe protein, realizing high efficiency (internal quantum yield >56 %), ATP‐independent, photon‐to‐fuel production, achieving an electron turnover number of >900, that is 72 % compared to the natural ATP‐coupled transformation of CO into hydrocarbons by V‐nitrogenase. The selectivity of products can be controlled by irradiation conditions, with higher photon flux favoring (longer‐chain) hydrocarbon generation. The CZS : VFe biohybrids not only can find applications in industrial CO removal for high‐value‐added chemical production by using the cheap, renewable solar energy, but also will inspire related research interests in understanding the molecular and electronic processes in photo‐biocatalytic systems.
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Nitrogen‐doped carbon dots from Kraft lignin waste with inorganic acid catalyst and their brain cell imaging applications
Abstract Carbon quantum dots (C‐QDs) show potential to replace traditional semiconductive quantum dots as the next generation of fluorescent probes. We demonstrate here a new C‐QD production process using lignin, a high‐volume but low market‐value industrial waste and/or environmental hazards, as the starting carbon source. By adding a small amount of inorganic acid, the rich phenolic components in lignin were successfully converted to C‐QDs through a coking formation mechanism similar to what happens on solid acid catalysts in traditional fossil fuel cracking process. Their aqueous solution presence of the received lignin C‐QDs is beneficial for brain cell imaging applications, attributing to their fast internalization, low toxicity, tunable photoluminescence by appropriate acidity and reaction temperature during hydrothermal synthesis. This method not only provides a low‐cost C‐QDs production route, but also helps gain extra profit and/or improve environment for many small agricultural business and paper and pulp industry located in rural area.
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- Award ID(s):
- 1662735
- PAR ID:
- 10452809
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- AIChE Journal
- Volume:
- 67
- Issue:
- 5
- ISSN:
- 0001-1541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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