Dataset Information

Atomic-Scale Tuning of Graphene/Cubic SiC Schottky Junction for Stable Low-Bias Photoelectrochemical Solar-to-Fuel Conversion.

ABSTRACT: Engineering tunable graphene-semiconductor interfaces while simultaneously preserving the superior properties of graphene is critical to graphene-based devices for electronic, optoelectronic, biomedical, and photoelectrochemical applications. Here, we demonstrate this challenge can be surmounted by constructing an interesting atomic Schottky junction via epitaxial growth of high-quality and uniform graphene on cubic SiC (3C-SiC). By tailoring the graphene layers, the junction structure described herein exhibits an atomic-scale tunable Schottky junction with an inherent built-in electric field, making it a perfect prototype to systematically comprehend interfacial electronic properties and transport mechanisms. As a proof-of-concept study, the atomic-scale-tuned Schottky junction is demonstrated to promote both the separation and transport of charge carriers in a typical photoelectrochemical system for solar-to-fuel conversion under low bias. Simultaneously, the as-grown monolayer graphene with an extremely high conductivity protects the surface of 3C-SiC from photocorrosion and energetically delivers charge carriers to the loaded cocatalyst, achieving a synergetic enhancement of the catalytic stability and efficiency.

SUBMITTER: Li H

PROVIDER: S-EPMC7304924 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Atomic-Scale Tuning of Graphene/Cubic SiC Schottky Junction for Stable Low-Bias Photoelectrochemical Solar-to-Fuel Conversion.

Li Hao H Shi Yuchen Y Shang Huan H Wang Weimin W Lu Jun J Zakharov Alexei A AA Hultman Lars L Uhrberg Roger I G RIG Syväjärvi Mikael M Yakimova Rositsa R Zhang Lizhi L Sun Jianwu J

ACS nano 20200407 4

Engineering tunable graphene-semiconductor interfaces while simultaneously preserving the superior properties of graphene is critical to graphene-based devices for electronic, optoelectronic, biomedical, and photoelectrochemical applications. Here, we demonstrate this challenge can be surmounted by constructing an interesting atomic Schottky junction <i>via</i> epitaxial growth of high-quality and uniform graphene on cubic SiC (3C-SiC). By tailoring the graphene layers, the junction structure de ...[more]

PMID: 32243124

Similar Datasets

Project description:Biochemical networks use reaction cascades to selectively reduce CO2 using energy from sunlight, but can similar selectivity be achieved by applying a cascade approach to an engineered system? Here, we report the design and implementation of a two-step photoelectrochemical (PEC) cascade to a liquid solar fuel: reduction of CO2 to CO and subsequent reduction of CO to methanol. The potentials required to perform the reductions were generated using custom-made III-V-based three-terminal tandem (3TT) solar cells. Cobalt phthalocyanine immobilized on multiwalled carbon nanotubes (CoPc/MWCNT) catalyzed both reactions. Multiphysics simulations of electrolyte flow and nonilluminated electrochemical measurements were used to narrow the operating parameters for the CoPc/MWCNT 3TT photocathodes. The champion integrated photocathode produced methanol with 3.8 ± 0.4% Faradaic efficiency (FE), with tested photocathodes having 0.7-3.8% methanol FE. Products were quantified by nuclear magnetic resonance spectroscopy and gas chromatography. The current output of the tested photocathodes was highly stable, and methanol production continued over multiple experiments. The low methanol yield is attributed to insufficient CO flux to, and CO2 depletion at, the methanol-producing subcell when both contacts are active, which is supported by the observation that a control photoelectrode slightly outperformed the methanol production of the 3TT device. Methanol production ceased when the 3TT subcell driving CO reduction was deactivated, supporting the assignment of a cascade mechanism. The major factors resulting in low methanol FE by the CoPc/MWCNT 3TT photocathodes are insufficient CO2 depletion at the methanol-producing contact and uncertainty in operating potential selection using the 3TT design. Although the CoPc/MWCNT 3TT photocathode is not yet highly selective, this work develops the basic science principles underlying the PEC cascade, demonstrates the co-design of a 3TT-based photoelectrode to produce carbon-based fuels, and finally discusses routes for improving product yields with this concept, including CO2 supply optimization and alternative photoelectrode and catalyst materials.

Dataset Information

Atomic-Scale Tuning of Graphene/Cubic SiC Schottky Junction for Stable Low-Bias Photoelectrochemical Solar-to-Fuel Conversion.

Publications

Atomic-Scale Tuning of Graphene/Cubic SiC Schottky Junction for Stable Low-Bias Photoelectrochemical Solar-to-Fuel Conversion.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets