Orientation of photosystem I on graphene through cytochrome c553 leads to improvement in photocurrent generation

Here, we report the development of a novel photoactive biomolecular nanoarchitecture based on the genetically engineered extremophilic photosystem I (PSI) biophotocatalyst interfaced with a single layer graphene via pyrene-nitrilotriacetic acid self-assembled monolayer (SAM). For the oriented and stable immobilization of the PSI biophotocatalyst, an His6-tag was genetically engineered at the N-terminus of the stromal PsaD subunit of PSI, allowing for the preferential binding of this photoactive complex with its reducing side towards the graphene monolayer. This approach yielded a novel robust and ordered nanoarchitecture designed to generate an efficient direct electron transfer pathway between graphene, the metal redox center in the organic SAM and the photo-oxidized PSI biocatalyst. The nanosystem yielded an overall current output of 16.5 µA·cm−2 for the nickel- and 17.3 µA·cm−2 for the cobalt-based nanoassemblies, and was stable for at least 1 h of continuous standard illumination. The novel green nanosystem described in this work carries the high potential for future applications due to its robustness, highly ordered and simple architecture characterized by the high biophotocatalyst loading as well as simplicity of manufacturing.

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Sunlight-assisted tailoring of surface nanostructures on single-layer graphene nanosheets for highly efficient cation capture and high-flux desalination

Carbon ◽

10.1016/j.carbon.2020.01.112 ◽

2020 ◽

Vol 161 ◽

pp. 674-684 ◽

Cited By ~ 2

Author(s):

Lei Zhang ◽

Xiangang Hu ◽

Qixing Zhou

Keyword(s):

Graphene Nanosheets ◽

Single Layer ◽

Single Layer Graphene ◽

High Flux ◽

Layer Graphene ◽

Highly Efficient ◽

Surface Nanostructures

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Comparative study of electron transfer on various graphene-metallic contacts

Modern Physics Letters B ◽

10.1142/s0217984919503846 ◽

2019 ◽

Vol 33 (31) ◽

pp. 1950384

Author(s):

Di Lu ◽

Yu-E Yang ◽

Weichun Zhang ◽

Caixia Wang ◽

Jining Fang ◽

...

Keyword(s):

Electron Transfer ◽

Single Layer ◽

Annealing Treatment ◽

Single Layer Graphene ◽

Strain Effect ◽

Graphene Surface ◽

Layer Graphene ◽

Metallic Contacts ◽

Nonuniform Strain ◽

Main Factor

We have investigated Raman spectra of the G and 2D lines of a single-layer graphene (SLG) with metallic contacts. The shift of the G and 2D lines is correlated to two different factors. Before performing annealing treatment or annealing under low temperature, the electron transfer on graphene surface is dominated by nonuniform strain effect. As the annealing treatment is enhanced, however, a suitable annealing treatment can eliminate the nonuniform strain effect where the relative work function (WF) between graphene and metal becomes a main factor to determine electronic transfer. Moreover, it is confirmed that the optimized annealing treatment can also decrease effectively the structural defect and induced disorder in graphene due to metallic contacts.

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Hybrid dye sensitized solar cell based on single layer graphene quantum dots

Dyes and Pigments ◽

10.1016/j.dyepig.2019.108118 ◽

2020 ◽

Vol 175 ◽

pp. 108118 ◽

Cited By ~ 3

Author(s):

Farhad Jahantigh ◽

S.M. Bagher Ghorashi ◽

Amir Bayat

Keyword(s):

Quantum Dots ◽

Solar Cell ◽

Graphene Quantum Dots ◽

Single Layer ◽

Single Layer Graphene ◽

Dye Sensitized Solar Cell ◽

Dye Sensitized ◽

Layer Graphene

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Millisecond lattice gasification for high-density CO2- and O2-sieving nanopores in single-layer graphene

Science Advances ◽

10.1126/sciadv.abf0116 ◽

2021 ◽

Vol 7 (9) ◽

pp. eabf0116

Author(s):

Shiqi Huang ◽

Shaoxian Li ◽

Luis Francisco Villalobos ◽

Mostapha Dakhchoune ◽

Marina Micari ◽

...

Keyword(s):

Single Layer ◽

High Density ◽

Single Layer Graphene ◽

Pore Density ◽

Vacancy Defects ◽

Carbon Gasification ◽

Layer Graphene ◽

Gas Molecules ◽

Good Agreement

Etching single-layer graphene to incorporate a high pore density with sub-angstrom precision in molecular differentiation is critical to realize the promising high-flux separation of similar-sized gas molecules, e.g., CO2 from N2. However, rapid etching kinetics needed to achieve the high pore density is challenging to control for such precision. Here, we report a millisecond carbon gasification chemistry incorporating high density (>1012 cm−2) of functional oxygen clusters that then evolve in CO2-sieving vacancy defects under controlled and predictable gasification conditions. A statistical distribution of nanopore lattice isomers is observed, in good agreement with the theoretical solution to the isomer cataloging problem. The gasification technique is scalable, and a centimeter-scale membrane is demonstrated. Last, molecular cutoff could be adjusted by 0.1 Å by in situ expansion of the vacancy defects in an O2 atmosphere. Large CO2 and O2 permeances (>10,000 and 1000 GPU, respectively) are demonstrated accompanying attractive CO2/N2 and O2/N2 selectivities.

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