Covalent organic framework (COF) membranes provide a highly tunable platform for molecular separation and interfacial regulation, but their performance is governed by coupled effects of pore geometry, chemical functionality, structural dynamics, and aqueous stability. Here, we develop an integrated multiscale modeling and data-driven framework for the discovery of functional COF membranes. First, non-equilibrium molecular dynamics simulations are used to predict water permeance and boron rejection under desalination conditions. By systematically varying pore size, functional groups, and framework structures, we establish structure–performance relationships and identify descriptors controlling membrane selectivity and transport.  Second, ab initio molecular dynamics simulations reveal how neutral, cationic, anionic, and mixed-charge COFs regulate water organization, CO₂ enrichment, and K⁺ distributions at COF/Cu interfaces. Enhanced CO₂-to-multicarbon activity emerges from a balanced interfacial environment rather than maximization of any single factor. Finally, we establish a hydrostability-aware screening pipeline that combines literature-derived stability criteria with pore-limiting diameter calculations using Zeo++ and PoreBlazer. Taken together, this framework links molecular-level understanding, performance prediction, and experimental feasibility to the rational design of scalable COF membrane systems.

Carbon capture remains a central challenge in decarbonizing energy-intensive industries. Membrane-based separation offers an energy-efficient alternative.

In this poster, we will present our work in advancing MOF-based mixed matrix membrane membranes for carbon capture by addressing the challenges of both materials and thin film coating. To enhance the intrinsic separation performances, polymer-MOF mixtures forming network structures were prepared. The impact of MOF particle size and the extent of networking were explored. Furthermore, different coating methods were applied to enable sub-100 nm coating on flat sheet and hollow fiber membranes. The membranes demonstrated impressive permeance and selectivity, and improved stability at higher temperatures (~ 3000 GPU of CO₂ permeance, > 25 selectivity at 60 degree Celcius). We further extended the efforts to MOC-based mixed matrix membranes, where structural re-alignment and gate-keeping effects by MOC are observed.

The selective separation of multivalent cations is important for desalination, brine management, and resource recovery. However, conventional cation-exchange membranes (CEMs) have limited ability to precisely distinguish between monovalent and multivalent ions or among multivalent ions with the same charge. This work explores novel composite CEMs based on two complementary bottom-up design strategies. Because membrane selectivity is primarily governed by ion partitioning and diffusion, we independently tailor membrane chemistry and structure to control these two mechanisms. Functional groups with tailored coordination properties regulate ion partitioning by promoting preferential interactions with target ions, while engineered transport pathways control ion diffusion according to properties such as hydrated size and mobility. The relationships among membrane composition, interfacial chemistry, water uptake, electrical resistance, and competitive ion transport are systematically investigated to identify the mechanisms governing selectivity. The resulting membranes could be integrated with electrodialysis and other electrically driven processes for the selective removal or recovery of multivalent ions, including calcium, zinc, and copper, from complex water streams. By combining molecular-level selectivity with scalable membrane fabrication, this research aims to transform ion-exchange membranes from conventional salt barriers into practical platforms for selective separation and circular resource recovery.

Addressing resource recovery and water pollution treatment through sustainable and environmentally friendly strategies is a significant global challenge. Our research focuses on developing low-carbon, renewable functional materials from biomass and bio-based polymers for resource recovery and water pollution treatment. For resource recovery, we have developed a series of biomass-based metal adsorbents for the selective extraction of elements such as lithium, rubidium, and cesium from seawater and other brines. For water pollution treatment, we have explored an environmentally friendly enzyme-based catalytic system by combining biochar (BC) with hydrogels to encapsulate horseradish peroxidase (HRP). Overall, our study utilises low-carbon, renewable materials and multiple regulation strategies to significantly improve resource recovery efficiency and pollutant degradation performance, offering a promising and environmentally friendly solution for resource extraction and water treatment.

Harmful algal blooms are an increasing challenge for seawater desalination, as elevated algae concentrations can cause severe membrane fouling, increase operational instability, and place greater demands on pretreatment processes. Conventional seawater pretreatment commonly employs dissolved air flotation followed by polymeric membrane filtration. However, this approach can be energy-intensive and requires a relatively large process footprint. In-line coagulation coupled with ceramic membrane filtration offers a promising alternative, potentially reducing footprint and energy consumption while benefiting from the longer lifespan, chemical resistance, and robustness of ceramic membranes. This study investigated the performance and fouling behaviour of this process at algae concentrations ranging from 20 to 200 ppb chlorophyll-a (Chl-a), with particular emphasis on fouling control through aeration and membrane cleaning. Stable filtration was achieved under normal seawater and low-algae conditions, while optimisation of aeration and membrane cleaning improved system resilience at elevated algae concentrations. Interestingly, fouling was less severe at 200 ppb Chl-a than at 100 ppb Chl-a, suggesting that fouling severity does not necessarily increase proportionally with algae concentration. Fouling analysis indicated a shift in the dominant fouling mechanism at high algae concentrations. Overall, the findings demonstrate the potential of in-line coagulation–ceramic membrane filtration as a compact and robust pretreatment strategy for seawater desalination under increasingly challenging algae bloom conditions.

As the seawater desalination industry is embracing more resilient solutions to address the more challenging seawater quality driven by the escalating climate change, conventional pre-treatment processes using chemical coagulation (CC) followed by polymeric ultrafiltration (UF) are no longer deemed adequate. Our previous work demonstrated that replacing CC with EC could reduce the polymeric UF fouling by up to 35%, while maintaining similar robust removals. In this study, we introduce, for the first time, electro-coagulation (EC) coupled with ceramic UF as a new alternative for SWRO pre-treatment. Technical feasibility was evaluated through bench-scale tests using raw and algae-laden seawater to simulate normal and algae-bloom conditions. Performance comparison was also conducted between EC-CUF and CC-CUF. Results showed that EC-CUF could produce consistent SWRO-feed-grade permeate with low turbidity and chlorophyll-a (< 5 ppb). In addition, EC-CUF exhibited markedly less UF fouling, and reduced operating costs. A continuous lab-scale EC-CUF system was examined as well, demonstrating the practical feasibility and scalability. The combination shows strong potential of EC-CUF as a resilient, lower-cost and scalable SWRO pre-treatment process.