Publications de Shaoxian Li | EPFL Graph Search

Nanolithography of the nanocorral structure of chemisorbed oxygen atoms on the graphitic lattice

Controlled atomic patterning is an attractive tool to fine tune properties of graphitic lattice. Several O-functionalized derivatives of graphitic lattice have been widely studied, e.g., graphene oxide, reduced graphene oxide, and functionalized carbon nan ...

Pergamon-Elsevier Science Ltd2024

Graphene membranes with pyridinic nitrogen at pore edges for high-performance CO2 capture

Andreas Züttel, Kumar Varoon Agrawal, Shiqi Huang, Luis Francisco Villalobos Vazquez de la Parra, Heng-Yu Chi, Shaoxian Li, Kuang-Jung Hsu, Marina Micari, Xuekui Duan, Liping Zhong, Shuqing Song

Membranes based on a porous two-dimensional selective layer offer the potential to achieve exceptional performance to improve energy efficiency and reduce the cost for carbon capture. So far, separation from two-dimensional pores has exploited differences ...

Nature Portfolio2024

Tuning Pore Size in Graphene in the Angstrom Regime for Highly Selective Ion-Ion Separation

Kumar Varoon Agrawal, Luis Francisco Villalobos Vazquez de la Parra, Heng-Yu Chi, Wan-Chi Lee, Shaoxian Li, Kuang-Jung Hsu, Kangning Zhao, Yuyang Zhang

Zero-dimensional pores spanning only a few angstroms in size in two-dimensional materials such as graphene are some of the most promising systems for designing ion-ion selective membranes. However, the key challenge in the field is that so far a crack-free ...

Amer Chemical Soc2024

Selective Photonic Gasification of Strained Oxygen Clusters on Graphene for Tuning Pore Size in the Å Regime

Oleg Yazyev, Luc Sébastien Bondaz, Kumar Varoon Agrawal, Kristians Cernevics, Shaoxian Li, Jian Hao

Controlling the size of single-digit pores, such as those in graphene, with an & Aring; resolution has been challenging due to the limited understanding of pore evolution at the atomic scale. The controlled oxidation of graphene has led to & Aring;-scale p ...

AMER CHEMICAL SOC2023

Mechanistic study on the evolution of vacancies in graphene by oxidation by scanning tunneling microscopy

Shaoxian Li

Nanostructured graphitic materials, including graphene hosting Å to nanometer-sized pores, have attracted attention for various applications such as separations, sensors, and energy storage. Graphene with Å-scale pores is a promising next-generation materi ...

EPFL2023

Periodate activation with copper oxide nanomaterials for the degradation of ciprofloxacin- A new insight into the efficiency and mechanisms

Shaoxian Li, Xi Zhang

In this study, CuO was synthesized using a facile precipitation method and was characterized using various techniques for the efficient activation of periodate (PI). Compared to systems consisting of PI alone (0.5 mM) and CuO alone (0.5 g/L), the CuO (0.5 ...

ELSEVIER SCI LTD2023

Unraveling the Oxidation of a Graphitic Lattice: Structure Determination of Oxygen Clusters

Nicola Marzari, Kumar Varoon Agrawal, Shiqi Huang, Shaoxian Li

Unraveling the oxidation of graphitic lattice is of great interest for atomic-scale lattice manipulation. Herein, we build epoxy cluster, atom by atom, using Van der Waals' density-functional theory aided by Clar's aromatic it-sextet rule. We predict the f ...

Amer Physical Soc2023

Unit-cell-thick zeolitic imidazolate framework films for membrane application

Yu Han, Deepu Joseph Babu, Kumar Varoon Agrawal, Luis Francisco Villalobos Vazquez de la Parra, Heng-Yu Chi, Shaoxian Li, Qi Liu, Jian Hao, Shuqing Song

Zeolitic imidazolate frameworks (ZIFs) are a subset of metal-organic frameworks with more than 200 characterized crystalline and amorphous networks made of divalent transition metal centres (for example, Zn2+ and Co2+) linked by imidazolate linkers. ZIF th ...

NATURE PORTFOLIO2023

Mechanistic Insights on Functionalization of Graphene with Ozone

Nicola Marzari, Luc Sébastien Bondaz, Kumar Varoon Agrawal, Shiqi Huang, Shaoxian Li, Kuang-Jung Hsu, Nicéphore Arthur François Bonnet

The exposure of graphene to O-3 results in functionalization of its lattice with epoxy, even at room temperature. This reaction is of fundamental interest for precise lattice patterning, however, is not well understood. Herein, using van der Waals density ...

Amer Chemical Soc2023

In Situ Nucleation-Decoupled and Site-Specific Incorporation of angstrom-Scale Pores in Graphene Via Epoxidation

Nicola Marzari, Luc Sébastien Bondaz, Kumar Varoon Agrawal, Shiqi Huang, Mohammad Tohidivahdat, Luis Francisco Villalobos Vazquez de la Parra, Heng-Yu Chi, Shaoxian Li, Kuang-Jung Hsu, Victor Carle Adrien Boureau

Generating pores in graphene by decoupled nucleation and expansion is desired to achieve a fine control over the porosity, and is desired to advance several applications. Herein, epoxidation is introduced, which is the formation of nanosized epoxy clusters ...

Wiley-V C H Verlag Gmbh2022

Structure Evolution of Graphitic Surface upon Oxidation: Insights by Scanning Tunneling Microscopy

Mounir Driss Mensi, Nicola Marzari, Kumar Varoon Agrawal, Shiqi Huang, Mohammad Tohidivahdat, Shaoxian Li, Kuang-Jung Hsu

Oxidation of graphitic materials has been studied for more than a century to synthesize materials such as graphene oxide, nanoporous graphene, and to cut or unzip carbon nanotubes. However, the understanding of the early stages of oxidation is limited to t ...

AMER CHEMICAL SOC2022

Systematic design of millisecond gasification reactor for the incorporation of gas-sieving nanopores in single-layer graphene

Kumar Varoon Agrawal, Shiqi Huang, Luis Francisco Villalobos Vazquez de la Parra, Shaoxian Li, Kuang-Jung Hsu

Etching an ensemble of vacancy defects (nanopores) in single-layer graphene (SLG) to obtain a high density of nanopores with an effective size that enables high-performance gas sieving is challenging. This is because nanopore nucleation and expansion are u ...

2021

Bottom-up synthesis of graphene films hosting atom-thick molecular-sieving apertures

Emad Oveisi, Mina Moradi, Kumar Varoon Agrawal, Shiqi Huang, Mostapha Dakhchoune, Luis Francisco Villalobos Vazquez de la Parra, Shaoxian Li, Kuang-Jung Hsu, Victor Carle Adrien Boureau, Kangning Zhao, Cédric Karel J Van Goethem

Incorporation of a high density of molecular-sieving nanopores in the graphene lattice by the bottom-up synthesis is highly attractive for high-performance membranes. Herein, we achieve this by a controlled synthesis of nanocrystalline graphene where incom ...

National Academy of Sciences2021

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

Mounir Driss Mensi, Emad Oveisi, Deepu Joseph Babu, Kumar Varoon Agrawal, Shiqi Huang, Mostapha Dakhchoune, Luis Francisco Villalobos Vazquez de la Parra, Shaoxian Li, Marina Micari

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 ki ...

2021

Atomic-scale insights into the origin of rectangular lattice in nanographene probed by scanning tunneling microscopy

Shaoxian Li

We conducted atomic-scale scanning tunneling microscopy of a graphene nanosheet on graphite. In addition to a rhombus lattice representing the (root 3x root 3)R30 degrees superstructure, we resolved another quadrangle lattice similar to a rectangle in the ...

AMER PHYSICAL SOC2021

Hydrogen-sieving single-layer graphene membranes obtained by crystallographic and morphological optimization of catalytic copper foil

Kumar Varoon Agrawal, Shiqi Huang, Shaoxian Li

Gas separation membranes based on single-layer-graphene are highly attractive because the size of graphene nanopores can be tuned to separate gases by the size-sieving mechanism. A prerequisite for this, the synthesis of high-quality polycrystalline single ...

2020