POROUS MATERIALs
for
Sustainable Chemical Technologies
Huan DOAN, PhD MRSC
Research Fellow, Australian National University
I am currently working as a Research Fellow at the Australian National University. Prior to this role, I spent time at the University of Bristol, first as a Research Associate (2019-2020) and later as an EPSRC Doctoral Prize Fellow from 2020 to 2023.
My academic journey began with a BSc and MSc in Chemical Engineering from the Hanoi University of Mining and Geology, Vietnam, in 2009 and 2012 respectively. This was followed by an MRes in Sustainable Chemical Technologies from the University of Bath, UK, in 2015. I completed my academic odyssey with a PhD in Mechanical Engineering in 2019 from the University of Bristol.
My research primarily revolves around the synthesis and characterisation of porous materials—including metal-organic frameworks, zeolites, and functional silicas. I harness these materials to address pressing challenges in sustainable development, particularly in areas of catalysis, gas separation, and energy storage.
Beyond research, I'm deeply committed to promoting science and inclusivity in academia. Currently, I co-chair the Vietnam Young Academy and act as an External Advisor for the Global Science Journey. I'm also a mentor with Lead The Change, where I champion STEM education in Vietnam. While at the University of Bristol, I co-chaired the BAME STEM Staff Network, advocating for diversity in the academic landscape.
I am passionate about outreach, having engaged with prospective students, research institutes, industry professionals, government representatives, media, and the broader public. A testament to my dedication is my achievement in the 3-Minute Thesis competition at the University of Bristol in 2017, where I reached the semi-finals. I also had the privilege of presenting my work to MPs at the esteemed STEM for BRITAIN event in 2019.
Over the years, my efforts have been acknowledged and celebrated. In 2019, I was honoured with the Inspirational Bristol Scientist Award. This was followed by an Honourable Mention at the UK-wide Doctoral Researcher Award competition in 2020.
MY CURRENT RESEARCH
Introducing heterostructure to graphitic carbon nitrides (g-C3N4) can improve the activity of visible-light-driven catalysts for efficient treatment of multiple toxic pollutants in water. Here we report for the first time that a complex material can be constructed from an oxygen-doped g-C3N4 and MIL-53(Fe) metal-organic framework using a facile hydrothermal synthesis and recycled polyethylene terephthalate from plastic waste. The novel multi-walled nanotube structure of the O-g-C3N4/MIL-53(Fe) composite which enables unique interfacial charge transfer at the heterojunction showed an obvious enhancement in separation efficiency of the photochemical electron-hole pairs. This resulted in narrow bandgap energy (2.30 eV compared to 2.55 eV in O-g-C3N4), high photocurrent intensity (0.17 mA cm-2 compared to 0.12 mA cm-2 and 0.09 mA cm-2 in MIL-53(Fe) and O-g-C3N4, respectively), and excellent catalytic performance in the photodegradation of anionic azo dyes (95% RR 195 and 99% RY 145 degraded after 4 h, and only a minor change in the efficiency observed after four consecutive tests). These results demonstrate the development of new catalysts made from waste feedstocks that show high stability, ease of fabrication and can operate in natural light for environmental remediation.
Introducing hierarchical pore structure to microporous materials such as metal-organic frameworks (MOFs) can be beneficial for reactions where the rate of reaction is limited by low rates of diffusion or high pressure drop. This advantageous pore structure can be obtained by defect formation, mostly via post-synthetic acid etching, which has been studied extensively on water-stable MOFs. Here we show that a water-unstable HKUST-1 MOF can also be modified in a corresponding manner by using phosphoric acid as a size-selective etching agent and a mixture of dimethyl sulfoxide and methanol as a dilute solvent.
Interestingly, we demonstrate that the etching process which is time- and acidity- dependent, can result in formation of defective HKUST-1 with extra interconnected hexagonal macropores without compromising on the bulk crystallinity. These findings suggest an intelligent scalable synthetic method for formation of hierarchical porosity in MOFs that are prone to hydrolysis, for improved molecular accessibility and diffusion for catalysis.
This work concerns the rapid synthesis of an archetypical metal-organic framework (MOF) material (HKUST-1) whereby the addition of supercritical CO2. The advantages of this method are that it allows a drastic reduction in the amounts of conventional solvents required for synthesis whilst removing the need for a separate post-synthetic solvent removal step and affording control over macroporosity in the resulting crystallites.
ANNUAL REPORTS
