Publications de Kuang-Jung Hsu

Non-van-der-Waals Oriented Two-Dimensional UiO-66 Films by Rapid Aqueous Synthesis at Room Temperature

Wendy Lee Queen, Kumar Varoon Agrawal, Heng-Yu Chi, Qi Liu, Kuang-Jung Hsu, Kangning Zhao, Shuqing Song, Ranadip Goswami

The synthesis of MOFs in a two-dimensional (2D) film morphology is attractive for several applications including molecular and ionic separation. However, 2D MOFs have only been reported from structures that crystallize in lamellar morphology, where layers ...

2025

Modulation of Graphene Oxidation Using Substrate-Induced Electron-Hole Puddles for Advancing Molecular Separation

Kumar Varoon Agrawal, Shiqi Huang, Heng-Yu Chi, Kuang-Jung Hsu, Ranadip Goswami

Tuning the reactivity of graphene enables molecular-level engineering of the lattice, achieving desired chemical and structural properties through functionalization, doping, and etching. Atom-thin graphene film hosting Å-scale pores, with capability to dif ...

2025

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

Electrochemical-repaired porous graphene membranes for precise ion-ion separation

Kumar Varoon Agrawal, Heng-Yu Chi, Kuang-Jung Hsu, Kangning Zhao, Shuqing Song, Zongyao Zhou

The preparation of atom-thick porous lattice hosting & Aring;-scale pores is attractive to achieve a large ion-ion selectivity in combination with a large ion flux. Graphene film is an ideal selective layer for this if high-precision pores can be incorpora ...

Nature Portfolio2024

Functionalized Å-scale Pores in Graphene for Carbon Capture

Kuang-Jung Hsu

Single-layer graphene, hosting a high density of functionalized molecular-sieving atom-thick pores, is considered to be an excellent material for gas separation membranes. These functionalized atom-thick pores enable the shortest transport pathway across t ...

EPFL2024

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

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

Enhanced Water Evaporation from A-Scale Graphene Nanopores

Mounir Driss Mensi, Kumar Varoon Agrawal, Shiqi Huang, Mostapha Dakhchoune, Luis Francisco Villalobos Vazquez de la Parra, Wan-Chi Lee, Kuang-Jung Hsu

Enhancing the kinetics of liquid-vapor transition from nanoscale confinements is an attractive strategy for developing evaporation and separation applications. The ultimate limit of confinement for evaporation is an atom thick interface hosting angstrom-sc ...

AMER CHEMICAL SOC2022

Gas Separation Membranes with Atom-Thick Nanopores: The Potential of Nanoporous Single-Layer Graphene

Deepu Joseph Babu, Kumar Varoon Agrawal, Luis Francisco Villalobos Vazquez de la Parra, Kuang-Jung Hsu, Cédric Karel J Van Goethem

Gas separation is one of the most important industrial processes and is poised to take a larger role in the transition to renewable energy, e.g., carbon capture and hydrogen purification. Conventional gas separation processes involving cryogenic distillati ...

AMER CHEMICAL SOC2022

Demonstrating and Unraveling a Controlled Nanometer-Scale Expansion of the Vacancy Defects in Graphene by CO2

Kumar Varoon Agrawal, Luis Francisco Villalobos Vazquez de la Parra, Kuang-Jung Hsu

A controlled manipulation of graphene edges and vacancies is desired for molecular separation, sensing and electronics applications. Unfortunately, available etching methods always lead to vacancy nucleation making it challenging to control etching. Herein ...

Wiley-VCH 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

Rapid Gas Transport from Block-Copolymer Templated Nanoporous Carbon Films

Kumar Varoon Agrawal, Mostapha Dakhchoune, Jing Zhao, Luis Francisco Villalobos Vazquez de la Parra, Kuang-Jung Hsu, Marina Micari, Xuekui Duan

Porous carbon films, attributed to their superior thermal and chemical robustness, are attractive for a number of applications. In the context of molecular separation, a major focus has been on films where the effective pore diameter is lower than 1 nm, e. ...

AMER CHEMICAL SOC2021

Multipulsed Millisecond Ozone Gasification for Predictable Tuning of Nucleation and Nucleation-Decoupled Nanopore Expansion in Graphene for Carbon Capture

Mounir Driss Mensi, Kumar Varoon Agrawal, Shiqi Huang, Guangwei He, Mostapha Dakhchoune, Luis Francisco Villalobos Vazquez de la Parra, Heng-Yu Chi, Wan-Chi Lee, Kuang-Jung Hsu

Predictable and tunable etching of angstrom-scale nanopores in single-layer graphene (SLG) can allow one to realize high-performance gas separation even from similar-sized molecules. We advance toward this goal by developing two etching regimes for SLG whe ...

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