I am looking for Ph.D./M.S. students/research assistants/associates/student helpers for the following projects.

If you are interested in these projects, please email me your CV for discussion. Thank you.

List of funded projects involved in UEA

  1. Development of NiAl layered double hydroxide/N-doped graphene high energy and power densities solid-state supercapacitor, The Science and Technology Development Fund of Macau SAR (FDCT), FDCT-098/2015/A3, 2016.07.01-2019.06.30, 1,440,000 (MOP);  180,252 (USD); 136,992 (GBP); Co-I.

Project No.

Project Title


Grant Type/

Amount (KRW)

Project Date



Graphene supported nano-sized MnO2 catalysts for catalytic ozonation of toluene at ambient temperature

20 M





Teaching grant

20 M





3D 계층의 NiAl 이중수산화/N 도핑된 그래핀 나노복합체가 적층된 Ni 폼의 전극을 이용한 고층형 슈퍼캐패스터의 높은에너지 및 전력밀도

Development and applications of high energy and power densities solid-state supercapacitor devices utilizing electrodes of 3D hierarchical NiAl layered double hydroxide/N-doped graphene nanocomposite loaded on Ni foam (3,655 project applied; 1,055 project funded)

Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2014R1A1A2055740 )/USD 125,000; funding rate of 28% (1,055/3,655)




Maintenance and water quality monitoring contract for 16/F wetland at Hysan Place, Hong Kong

Consultancy project





Development and application of high energy and power densities solid-state supercapacitor device

Creative Grant, HYU 2015, 7 M KRW





Introduction of ABAQUS modelling skills in DME3052 Machine Elements Design

Hanyang University, 2 M KRW




Total funding: 127,787 (GBP); 166,360 (USD)

roject No.

Project Title


Grant Type/

Amount (HKD)

Project Date



Current Status on Energy Usage and Potential on Further Adoption of Renewable Energy in Various Cites in Asia

C011318 /

Industry, Ove Arup & Partners Hong Kong Ltd /






Development of Student-led Laboratory Experience

6000164 /

TDG, CityU /






Development of a Novel Mesoporous Fiber Matrix Based Air Purification Technology

9667024 /

ARG PI, CityU /






A Novel, Green and Fast Approach to Produce Nano-Material MCM-41: Process Optimization and Application of MCM-41 in Production of Bio-Ethanol

7200144 /

StUp, CityU /






Conversion of Rice Husk into Ethanol by a Novel and Green Approach Using Nano-porous Materials: Process Optimization

7002470 /

SRG, CityU /






A Novel, Green and Fast Approach to Produce Nano-sized MCM-41 from Coal Fly Ash: Process Optimization and Applications of MCM-41 in Air Purification

7008056 /

SRG-Fd, CityU /






Performance Study of Novel Adsorption Foams for Desiccant Cooling Applications

7002579 / SRG, CityU /






Performance assessment of plasma assisted catalytic oxidation based air purification technology for indoor VOCs removal

9667037 /

ARG PII, CityU /

1,275,000 (375,000 from a company)





Ozone-catalytic Oxidation System and Process Optimization for Indoor Air Purification

114310 /


607,477; funding rate of 31% (764/2,463)





Development of a Novel Ozone Catalytic Oxidation-based Dyeing Wastewater Treatment Technology

6351005 / I2RF, CityU / 400,000





Development of photonic crystal structure on transparent conducting oxide thin film for high brightness blue GaN LEDs

CFP, CityU / 100,000





Development of Self-Regenerating Catalysts in Ozone-Catalytic Oxidation System for Air Purification Applications

9667051 /

ARG PI, CityU /






Reliability study of GaN-based blue LEDs employing composite transparent conducting oxide with p-type conduction

9666010 / I2RF, CityU / 380,000





Development and investigation of a high-energy efficient ozone-catalytic oxidation based air purifier

ITS/244/11, Innovation and Technology Fund, Tier 3, HKSAR /

999,994 (from ITF);

521,138 (internship, ITF)

200,000 (from 2 companies)

173,912 (from CityU)








Ozone-Catalytic Oxidation Technology with Pd Nanoparticles Doped CO3O4 Nanowire Catalysts on Nickel Foam for Toluene Removal

9667065 /

ARG PI, CityU /






Fabrication and Characterization of Novel Palladium-graphene Composites and Their Performances in the Catalytic Ozonation of Toluene

7002825/ SRG-Fd, CityU /






Effectiveness of Installing Musical Staircases at CityU in Changing Behavior toward Environmental Sustainability

69860110/ Campus sustainability project , CityU / 300,000





Design, Supply and Construction of Artificial Wetland at 16/F Sky Garden of Hysan Place

9231109/ Contract research





Implementation of Student-oriented Rooftop Aquaponics to Promote Food Sustainability

6987021/ Campus sustainability project, CityU / 342,000





Engineering the surface properties and pore size distribution of porous graphene and understanding their influences on the capacitive performances of supercapacitor

7004081/ SRG-Fd, CityU /




  Total funding

942,400 (GBP); 1.24 million (USD)


Centre for System Informatics Engineering

Research Centres, CityU



Centre for Functional Photonics

Research Centres, CityU




Development of carbon nanotube embedded zeolite 13X/CaCl2 composite adsorbents for waste heat powered adsorption cooling systems

GRF, HKSAR, HKD 500,000;

65,000 (USD); 49,400 (GBP)




Development of high performance solid-state rigid/flexible supercapacitors

Energy storage (ES) was identified as one of the UK's Eight Great Technologies (Willets, 2013) because of its potential to help the UK meet emission targets by allowing greater penetration of all-electric vehicles to the mass market. UK energy storage industries have been looking for a low cost manufacturing process to produce advanced materials for high performance energy storage device such as supercapacitor and Li/Na ions battery.

We have extensive research experience in preparation, characterization and applications of hierarchical micro-, meso-porous materials, including porous carbon [1-4], graphene [5], nanoparticle/graphene composites [6-8], graphene aerogel [9, 10], metal oxides (NiO [11, 12], CuCo2O4/MnCo2O4 [13] and LDHs [14-17]), and metal oxides/graphene composites (carbon sphere [18], NiO [19], Co2(OH)2CO3 [20], (CuCo)2(CO3)(OH)2 [21], NiGa2O4 [22], MnCo2O4 [23-25], Ni(HCO3)2-MnCO3 [26] and LDHs [15, 27-29], LiNixMn1-xO4 [30-32]) in energy storage research.

We found that the synthesis conditions significantly influence the PSD, SSA, and N-, S-doping/surface oxygen functionalities of carbon/metal oxides electrodes, leading to an improved capacitive performance of the electrodes. In 3D hierarchical porous graphene aerogel (HPGA) research, we controlled the size of pores and density of pores on the surface of graphene nanosheets (GNS) to form a 3D porous structure, which facilitates electrolyte ions soaking into the electrode materials. The 3D HPGA-50 electrodes, with SSA of 383.7 m2/g and pore size of 53 nm, exhibited a high reversible specific capacitance of 1100 mAh/g at a current density of 0.1 A/g. Our developed synthesis method can (1) control the dimensions of well-defined meso-pores of GNS, (2) control the density of pores of GNS, and (3) increase the SSA of GNS. We explored and understood the pore formation mechanism, and the influences of PSD, SSA, and electrical conductivity on electrochemical properties of HPGA. The structural changes during long time charging/discharging cycles and their influences on the life cycle stability of electrodes were also investigated.

Our major contributions include 1) development of a green method for synthesis of graphene, 2) production of hierarchical N-doped porous carbon from biowastes as electrode materials for supercapacitors and 3) development of hierarchical well-defined mesoporous graphene aerogel for high performance (1100 mAh g-1) Li-ion battery.

Device (voltage)




Energy density (W h kg−1)

Power density of  (W kg−1)

Stability/retention (%)

Cycle@ current density


CR 2302 coin cell (1.6 V)

ultrathin NiAl-LDH nanosheet arrays on carbon nanotube paper

porous graphene nanosheets


50 (23.3)

467 (21.5 k)


5,000@5 A g−1

Chemical Engineering Journal, 325, pp. 554-563, 2017. link

CR 2302 coin cell (1.4 V)

ultrathin petal-like NiAl layered double oxide/sulfide







5,000@5 A g−1

Journal of Materials Chemistry A, 5, pp. 19687-19696, 2017. link




CR 2302 coin cell (1.6 V)

NiGa2O4 nanosheets

spindle-like Fe2O3





10,000@10 A g−1

Journal of Materials Chemistry A, 5, pp. 19046-19053, 2017. link


CR 2302 coin cell (1.4 V)

carbon@NiAl-LDH core–shell spheres as spacers among graphene layers (G-CLS)



35.5 (32.1)









670.7 (5578.1)





10,000@5 A g−1

ACS Applied Materials & Interfaces, 9 (2), pp. 1395–1406, 2017. link

CR 2302 coin cell (1.6 V)




85.7 (34.7)

800 (24,000)


8,000@10 A g−1

ChemNanoMat, 1, pp. 593-602, 2015.  link (featured on the Back Cover)

flexible solid-state supercapacitors

(1.6 V)

carbon nanotube@manganese oxide nanosheet core-shell structure film

holy graphene/carbon spheres film

PAAK/KCl gel

24.6 (17.7)

459.3 (9005.3)


10,000@10 A g−1

Carbon, 132, pp. 776–784, June 2018. link

flexible solid-state supercapacitors

(1.0 V)

Ag NWs@NiAl LDH core@shell
graphene hybrid


Ag NWs@NiAl LDH core@shell
graphene hybrid



(35.75 mWh cm-3)


(1.01 W cm-3)



10,000@5 A g−1

Chemical Engineering Journal, 348, pp. 338-349, 15 September 2018. link

flexible solid-state  supercapacitors (1.6 V)




46.5 (28.4)

526.9 (7876.9)


10,000@7 A g−1

Electrochimica Acta, 295, 1 February 2019, pp. 759-768, 2019. link

milliamp hour (mAh) and voltage (V) to obtain Watt hours (Wh):  (mAh)*(V)/1000 = (Wh)

Watts-hour (Wh) and voltage (V) to obtain milliamp-hours (mAh):  (Wh)*1000/(V) =(mAh) link



Electrolyte (gel)

Energy density

(W h kg−1)

Power density

(W kg−1)

Retention (%)/ Cycle@current



Retention (%)/ Bending cycle@angles


CuCo2S4 /C fiber

-tubular nanostructures (100 nm dia.)

MoO2@N-doped C/ C fiber

-tubular nanostructures (500 nm dia.)



65.1 (27.6)

800 (12,800)


5,000@16 A g−1


2000@(0°, 45°, 90°, 135°)

Advanced Science, 5, pp. 1800733, 2018. link


-nanorods: 40 nm dia.


P‐doped MoS2

-NWs: 100 nm dia.

-P (1.56 wt% (2.69 at%))


67.4 (22.5)

850 (13,600)


5,000@8 A g−1



Small, 15, 1803984, 2019.



F-Co2MnO4-x/ C fiber

-F (1.92 at%)



Fe2O3/ C fiber



64.4 (24.2)

800 (8,000)


5,000@15 A g−1



2000@(0°, 30°)


Energy Storage Materials, https://doi.org/10.1016/j.ensm.2018.10.022

P-CoMoO4-x on NF

-nanosheets (lateral size of ~600 nm and a thickness of ~20 nm)

-P (9.18at%)

Activated carbon

1 M KOH (aqueous)

58 (18.8)

850 (12,750)


10,000@10 A g−1


Energy Storage Materials, 19, pp. 186-196, May 2019. link


Inquiry: Please contact k.hui@uea.ac.uk for more information and quotation.



[1] X. Wu, X.T. Hong, Z. Luo, K.S. Hui, H. Chen, J. Wu, K.N. Hui, L. Li, Q. Zhang, J. Nan, "The effects of surface modification on the supercapacitive behaviors of novel mesoporous carbon derived from rod-like hydroxyapatite template," Electrochimica Acta, 89  pp. 400-406, 2012.

[2] X. Wu, X. Hong, J. Nan, Z. Luo, Q. Zhang, L. Li, H. Chen, K.S. Hui, "Electrochemical double-layer capacitor performance of novel carbons derived from SAPO zeolite templates," Microporous and Mesoporous Materials, 160  pp. 25-31, 2012.

[3] X. Wu, K.N. Hui, K.S. Hui, S.K. Lee, W. Zhou, R. Chen, D.H. Hwang, Y.R. Cho, Y.G. Son, "Adsorption of basic yellow 87 from aqueous solution onto two different mesoporous adsorbents," Chemical Engineering Journal, 180  pp. 91-98, 2012.

[4] X. Hong, K.S. Hui, Z. Zeng, K.N. Hui, L. Zhang, M. Mo, M. Li, "Hierarchical nitrogen-doped porous carbon with high surface area derived from endothelium corneum gigeriae galli for high-performance supercapacitor," Electrochimica Acta, 130 (0), pp. 464-469, 2014.

[5] H. Zhao, K.S. Hui, K.N. Hui, "Synthesis of nitrogen-doped multilayer graphene from milk powder with melamine and their application to fuel cells," Carbon, 76  pp. 1-9, 2014.

[6] C.H.A. Tsang, K.N. Hui, K.S. Hui, L. Ren, "Deposition of Pd/graphene aerogel on nickel foam as a binder-free electrode for direct electro-oxidation of methanol and ethanol," J Mater Chem A, 2 (42), pp. 17986-17993, 2014.

[7] L. Ren, K.S. Hui, K.N. Hui, "Self-assembled free-standing three-dimensional nickel nanoparticle/graphene aerogel for direct ethanol fuel cells," Journal of Materials Chemistry A, 1 (18), pp. 5689-5694, 2013.

[8] K.S. Hui, K.N. Hui, D.A. Dinh, C.H. Tsang, Y.R. Cho, W. Zhou, X. Hong, H.H. Chun, "Green synthesis of dimension-controlled silver nanoparticle-graphene oxide with in situ ultrasonication," Acta Materialia, 64  pp. 326-332, 2014.

[9] L. Ren, K.N. Hui, K.S. Hui, Y. Liu, X. Qi, J. Zhong, Y. Du, J. Yang, "3D hierarchical porous graphene aerogel with tunable meso-pores on graphene nanosheets for high-performance energy storage," Scientific Reports, 5  pp. 14229, 2015.

[10] Q. Bao, K.N. Hui, K.S. Hui, Y. Wang, X. Hong, "Hydrothermal self-assembly and supercapacitive behaviors of Co(II) ion-modified graphene aerogels in H2SO4 electrolyte," Materials Research Bulletin, 56  pp. 92-97, 2014.

[11] S.X. Wu, K.S. Hui, K.N. Hui, K.H. Kim, "Ultrathin porous NiO nanoflake arrays on nickel foam as an advanced electrode for high performance asymmetric supercapacitors," J. Mater. Chem. A, 4  pp. 9113-9123, 2016.

[12] S. Wu, K.S. Hui, K.N. Hui, J.M. Yun, K.H. Kim, "Silver particle-loaded nickel oxide nanosheet arrays on nickel foam as advanced binder-free electrodes for aqueous asymmetric supercapacitors," RSC Advances, 7 (66), pp. 41771-41778, 2017.

[13] S. Liu, K.S. Hui, K.N. Hui, "Flower-like Copper Cobaltite Nanosheets on Graphite Paper as High-Performance Supercapacitor Electrodes and Enzymeless Glucose Sensors," Acs Appl Mater Inter, 8 (5), pp. 3258-3267, 2016.

[14] L. Zhang, K.N. Hui, K.S. Hui, X. Chen, R. Chen, H. Lee, "Role of graphene on hierarchical flower-like NiAl layered double hydroxide-nickel foam-graphene as binder-free electrode for high-rate hybrid supercapacitor," Int J Hydrogen Energ, 41  pp. 9443-9453, 2016.

[15] L. Zhang, K.N. Hui, K.S. Hui, H. Lee, "Facile synthesis of porous CoAl-layered double hydroxide/graphene composite with enhanced capacitive performance for supercapacitors," Electrochim Acta, 186  pp. 522-529, 2015.

[16] C. Xing, F. Musharavati, H. Li, E. Zalezhad, O.K.S. Hui, S. Bae, B.-Y. Cho, "Synthesis, characterization, and properties of nickel-cobalt layered double hydroxide nanostructures," RSC Advances, 7 (62), pp. 38945-38950, 2017.

[17] L. Zhang, R. Chen, K.N. Hui, K.S. Hui, H. Lee, "Hierarchical ultrathin NiAl layered double hydroxide nanosheet arrays on carbon nanotube paper as advanced hybrid electrode for high performance hybrid capacitors," Chemical Engineering Journal, 325 (Supplement C), pp. 554-563, 2017.

[18] S. Wu, K.S. Hui, K.N. Hui, J.M. Yun, K.H. Kim, "A novel approach to fabricate carbon sphere intercalated holey graphene electrode for high energy density electrochemical capacitors," Chemical Engineering Journal, 317  pp. 461-470, 2017.

[19] Q.X. Xia, K.S. Hui, K.N. Hui, D.H. Hwang, S.K. Lee, W. Zhou, Y.R. Cho, S.H. Kwon, Q.M. Wang, Y.G. Son, "A facile synthesis method of hierarchically porous NiO nanosheets," Materials Letters, 69  pp. 69-71, 2012.

[20] X. Lin, H. Li, F. Musharavati, E. Zalnezhad, S. Bae, B.-Y. Cho, O.K.S. Hui, "Synthesis and characterization of cobalt hydroxide carbonate nanostructures," RSC Advances, 7 (74), pp. 46925-46931, 2017.

[21] S. Liu, K.S. Hui, K.N. Hui, V.V. Jadhav, Q.X. Xia, J.M. Yun, Y.R. Cho, R.S. Mane, K.H. Kim, "Facile Synthesis of Microsphere Copper Cobalt Carbonate Hydroxides Electrode for Asymmetric Supercapacitor," Electrochim Acta, 188  pp. 898-908, 2016.

[22] S. Liu, K.S. Hui, K.N. Hui, H.-F. Li, K.W. Ng, J. Xu, Z. Tang, S.C. Jun, "Asymmetric Supercapacitor with Excellent Cycling Performance Realized by Hierarchical Porous NiGa2O4 Nanosheets," Journal of Materials Chemistry A, 5  pp. 19046-19053, 2017.

[23] S. Liu, K.S. Hui, K.N. Hui, J.M. Yun, K.H. Kim, "Vertically Stacked Bilayer CuCo2O4/MnCo2O4 Heterostructures on Functionalized Graphite Paper for High-Performance Electrochemical Capacitors," J. Mater. Chem. A,   pp. DOI: 10.1039/C6TA00960C, 2016.

[24] S. Liu, K.S. Hui, K.N. Hui, "1D Hierarchical MnCo2O4 Nanowire@MnO2 Sheet Core-shell Arrays on Graphite Paper as Superior Electrode for Asymmetric Supercapacitor," ChemNanoMat,   pp. n/a-n/a, 2015.

[25] K.N. Hui, K.S. Hui, Z. Tang, V.V. Jadhav, Q.X. Xia, "Hierarchical chestnut-like MnCo2O4 nanoneedles grown on nickel foam as binder-free electrode for high energy density asymmetric supercapacitors," Journal of Power Sources, 330 (Supplement C), pp. 195-203, 2016.

[26] Q.X. Xia, K.S. Hui, K.N. Hui, S.D. Kim, J.H. Lim, S.Y. Choi, L.J. Zhang, R.S. Mane, J.M. Yun, K.H. Kim, "Facile synthesis of manganese carbonate quantum dots/Ni(HCO3)(2)-MnCO3 composites as advanced cathode materials for high energy density asymmetric supercapacitors," J Mater Chem A, 3 (44), pp. 22102-22117, 2015.

[27] S.X. Wu, K.S. Hui, K.N. Hui, "One-Dimensional Core-Shell Architecture Composed of Silver Nanowire@Hierarchical Nickel-Aluminum Layered Double Hydroxide Nanosheet as Advanced Electrode Materials for Pseudocapacitor," J Phys Chem C, 119 (41), pp. 23358-23365, 2015.

[28] L. Li, K.S. Hui, K.N. Hui, Y.R. Cho, "Ultrathin Petal-like NiAl Layered Double Oxide/Sulfide Composites as Advanced Electrode for High-performance Asymmetric Supercapacitor," Journal of Materials Chemistry A, 5  pp. 19687-19696, 2017.

[29] S.X. Wu, K.S. Hui, K.N. Hui, K.H. Kim, "Electrostatic-Induced Assembly of Graphene-Encapsulated Carbon@Nickel-Aluminum Layered Double Hydroxide Core-Shell Spheres Hybrid Structure for High-Energy and High-Power-Density Asymmetric Supercapacitor," ACS Appl. Mater. Interfaces, 9 (2), pp. 1395-1406, 2017.

[30] M. Mo, K.S. Hui, X. Hong, J. Guo, C. Ye, A. Li, N. Hu, Z. Huang, J. Jiang, J. Liang, H. Chen, "Improved cycling and rate performance of Sm-doped LiNi0.5Mn 1.5O4 cathode materials for 5 v lithium ion batteries," Applied Surface Science, 290  pp. 412-418, 2014.

[31] M. Mo, C. Ye, K. Lai, Z. Huang, L. Zhu, G. Ma, H. Chen, K.S. Hui, "Gelatin-assisted synthesis of LiNi0.5Mn1.5O 4 cathode material for 5V lithium rechargeable batteries," Applied Surface Science, 276  pp. 635-640, 2013.

[32] M.Y. Mo, H.Y. Chen, X.T. Hong, K.S. Hui, C.C. Ye, K. Lai, "Hydrothermal synthesis of reduced graphene oxide-LiNi0.5Mn1.5O4 composites as 5 V cathode materials for Li-ion batteries," J. Mater. Sci., 52 (5), pp. 2858-2867, 2017.


2 SS-HSCs power a LED (funded by HYU Creative Grant 2015)



2 SS-HSCs power a fan


2 SS-HSCs power a LED

Optimization of catalytic ozonation (CO) technology/system for VOCs removal.

Our work focused on developing a novel air purification technology for VOCs removal under room temperature (Fig. 1 shows the setup for the study). This work involves the oxidation reaction of selected VOCs (volatile organic compounds) and the different mass transfer mechanisms in the materials, giving to very complex phenomena. This work addresses the basic mechanisms of such process that remains poorly understood. We found that ozone decomposes into an active oxygen species on the Lewis acid sites of the adsorbents and subsequently reacts with toluene to form CO2 and H2O. The removal efficiency of the CO system was improved by loading nanocatalysts on different porous materials. In addition, the mechanisms of VOCs (e.g., toluene and methane) decomposition during the CO process were explored, thereby helping in the improvement of catalyst designs. In the CO process, the reaction by-products (e.g., aldehydes and organic acids) were found to occupy the catalyst active sites. These products are the major causes of the catalyst deactivation after prolonged use at room conditions. Moreover, methods for reducing the residual ozone to a safe level (< 50 ppb) were developed. Research on modeling the complex chemical reaction kinetics and heat/mass transfer behaviors in porous beds/catalytic systems has also been conducted. A multi-scale model that describes the coupling of mass transport and reaction kinetics has been developing to shed light on the underlying mechanisms of mass transport and reaction kinetics, and to optimize the design and operating parameters.

New insights from this study will be added to current understanding in the effects of different mass transfer mechanisms on the overall reaction kinetics. The effects of the operating and design parameters on the system performance, including the inlet reactant concentration, flow velocity, and reactor design, among others, have been investigated. With these works, the operating and design parameters of the proposed CO technology can be optimized to maximize the removal efficiency.

We believe that the proposed technology is a promising solution for VOCs removal in many applications. The air purifier to be developed offers three striking features: i) much lower operating temperature than conventional technologies, reducing energy consumption; ii) the enhanced VOC transport and adsorption, increasing the purification efficiency; iii) the reduced pressure drop, decreasing pump work and further saving the energy.

Fig. 1. The setup for the study of the proposed CO technology.

We have been developing some technologies for air treatment since 2004. Fig. 2 summarizes the related work conducted in air treatment.

Fig. 2. Related work conducted in air treatment.


  1. K.S. Hui, K.L. Tsui, M.O. Fu, "Gas treatment by catalytic ozone oxidation," US Patent US8568680B2. Filed: 8 Oct 2010; Date of Patent: 29 Oct 2013. link

  2. K.S. Hui, C.W. Kwong, C.Y.H. Chao, "Methane emission abatement by Pd-ion-exchanged zeolite 13X with ozone," Energy & Environmental Science, 3, pp. 1092-1098, 2010.  link

  3. M. Li, K.N. Hui, K.S. Hui, S.K. Lee, Y.R. Cho, Heesoo Lee, W. Zhou, Shinho Cho, C.Y.H. Chao, Y.Y. Li, "Influence of modification methods and transition metal type on the physicochemical properties of MCM-41 catalysts and their performances in the catalytic ozonation of toluene," Applied Catalysis B: Environmental, 107, pp. 245-252, 2011.  link

  4. M. Hu, K.S. Hui, K.N. Hui, “Role of graphene in MnO2/graphene composite for catalytic ozonation of toluene,” Chemical Engineering Journal, 254, pp. 237-244, 2014.  link

  5. M. Hu, Z. Yao, K. N. Hui and K. S. Hui, "Novel mechanistic view of catalytic ozonation of gaseous toluene by dual-site kinetic modelling," Chemical Engineering Journal, 308, pp. 710-718, 2017. link

License agreement with

ASA Innovation & Technology Ltd., Hong Kong

Inquiry: Please contact k.hui@uea.ac.uk for more information and quotation.

Development of advanced catalytic ozonation technology for water treatment

The ever-growing concerns about the quality and safety of water have motivated tremendous efforts in developing advanced water treatment technologies. Catalytic ozonation process has been developed to improve its performance owing to its higher effectiveness in the degradation and mineralization of refractory organic pollutants. In our studies, we found that graphene nanosheets not only functioned as a support for Co3O4 nanocrystals but also functioned as a co-catalyst for the enhancement in phenol removal efficiency. The surface nitridation and Co3O4 modification treatment further improved the removal rate of the phenol pollutants and brought in the higher oxidation degree. Our finding may open new perspectives for pursuing exceptional activity for catalytic ozonation reaction.

Fig. 1. The experimental setup used for the phenol degradation reaction in water solutions through the catalytic and non-catalytic ozonation processes.

Fig. 2. A scheme illustrating the possible mechanism for the catalytic ozonation of phenol at the presence of the Co3O4/NG nanocomposites.

We have been exploring other technologies/methods in water treatment, as shown in Fig. 3. Please check the related publications.

Inquiry: Please contact k.hui@uea.ac.uk for more information and quotation.

Fig. 3. A summary of materials used in water treatment.


Capacitive deionization (CDI): a new type of water treatment technology

CDI usually consists of two electrodes placed in parallel, as well as an aqueous solution containing ions that flows between or through the charging electrodes. When a certain voltage is applied between the two electrodes, a continuous stable electric field is generated between them; thereafter, the charged ions present in feed water migrate to the electrical double layer (EDL) under the electric field force. During this process, the charged ions (cations and anions) migrate toward the opposite electrode (cathode and anode); consequently, large amounts of ions are strongly electro-adsorbed on the surface of the electrode, leading to a decrease in the salinity of the solution and thereby improving water quality.


  • E. Zhu, X. Hong*, Z. Ye, K.S. Hui, K.N. Hui, "Influence of various experimental parameters on the capacitive removal of phosphate from aqueous solutions using LDHs/AC composite electrodes," Separation and Purification Technology, 215, pp. 454-46, 15 May 2019. link
  • X. Hong*, E. Zhu, Z. Ye, K.S. Hui, K.N. Hui, "Enhanced Phosphate Removal under an Electric Field via Multiple Mechanisms on MgAl-LDHs/AC Composite Electrode," Journal of Electroanalytical Chemistry, 836, pp. 16-23, 1 March 2019. link
  • D. Sun, X. Hong*, K. Wu, K.S. Hui, Y. Du, K.N. Hui, "Simultaneous removal of ammonia and phosphate by electro-oxidation and electrocoagulation using RuO2–IrO2/Ti and microscale zero-valent iron composite electrode," Water Research, 169, pp. 115239, 2019. link



  1. K.S. Hui, K.L. Tsui, M.O. Fu, "Gas treatment by catalytic ozone oxidation," US Patent US8568680B2. Filed: 8 Oct 2010; Date of Patent: 29 Oct 2013. link

  2. X. Wu, K.N. Hui, K.S. Hui, S.K. Lee, W. Zhou, "Adsorption of basic yellow 87 from aqueous solution onto two different mesoporous adsorbents," Chemical Engineering Journal, 180, pp. 91-98, 2012.  link

  3. H.R. Pant, H.J. Kim, M.K. Joshi, B. Pant, C.H. Park, J.I. Kim, K.S. Hui, C.S. Kim, “One-step fabrication of multifunctional composite polyurethane spider-web-like nanofibrous membrane for water purification,” Journal of Hazardous Materials, 264, pp. 25-33, 2014.  link

  4. S. Wu, J. Fang, X. Hong, K.S. Hui, Y. Chen, "Facile preparation and characterization of BiOI/rectorite composite with high adsorptive capacity and photocatalytic activity," Dalton Transactions, 43, pp. 2611-2619, 2014. link

  5. Qiangqiang Sun, Laisheng Li, Huihua Yan, Xiaoting Hong, K.S. Hui, Zhaoqi Pan, “Influence of the surface hydroxyl groups of MnOx/SBA-15 on heterogeneous catalytic ozonation of oxalic acid,” Chemical Engineering Journal, 242, pp. 348–356, 2014.  link

  6. S.N. Zhu, K.N. Hui, X. Hong, K.S. Hui, "Catalytic ozonation of basic yellow 87 with a reusable catalyst chip," Chemical Engineering Journal, 242, pp. 180-186, 2014.  link

  7. X. Hong, M. Li, S. Shan, K.S. Hui, M. Mo, and X. Yuan, "Chloride ion-driven transformation from Ag3PO4 to AgCl on the hydroxyapatite support and its dual antibacterial effect against Escherichia coli under visible light irradiation," Environmental Science and Pollution Research, 23, pp. 13458-13466, 2016.  link

  8. Q. Bao, K.S. Hui, J.G. Duh, "Promoting Catalytic Ozonation of Phenol over Graphene through Nitrogenation and Co3O4 Compositing," Journal of Environmental Sciences, 50, pp. 38–48, 2016. link

  9. Z. Ye*, M. Tang, X. Hong, and K.S. Hui, "Sustainable Composite Super Absorbents Made from Polysaccharides," Materials Letters, 183, pp. 394-396, 2016  Link

  10. X. Hong*, M. Li, S. Shan, K.S. Hui, M. Mo*, and X. Yuan, "Chloride ion-driven transformation from Ag3PO4 to AgCl on the hydroxyapatite support and its dual antibacterial effect against Escherichia coli under visible light irradiation," Environmental Science and Pollution Research, 23, pp. 13458-13466, 2016.  link

  11. X. Hong*, C. Fang, K.S. Hui, K.N. Hui, H. Zhuang, W. Liu, S. Shan*, "Influence of interfering anions on Cu2+ and Zn2+ ions removal on chestnut outer shell-derived hydrochars in aqueous solution," RSC Advances, 7 (81), pp. 51199-51205, 2017. link

Design, supply, and construction of artificial wetland at the 16/F Sky Garden of Hysan Place, Causeway Bay, Hong Kong, 2013-present


Client: Hysan Development Company Limited http://www.hysan.com.hk/



The artificial wetland system was specially designed, built and maintained to purify the greywater (max. 30 m3/day) for water reuse. The greywater is mainly collected from wash basins inside the office tower without coming into contact with toilet waste. After sedimentation, filtration, bio-chemical reactions, and disinfection (via UV), the treated greywater was used for irrigation. Greywater reuse has the potential to reduce the building’s carbon footprint and reduce the load on sewage treatment facilities.


The treated greywater can be discharged into Victoria Harbour Water Control Zone (Phase Three) via communal storm water drain (License No. WT00019582-2014; valid to 31 July 2019).


Keywords: Grey water; biological/aerobic treatment; filtration; disinfection (chlorine, sodium hypochlorite, UV); plant; irrigation; floor cleansing


Funding source: Hysan via PJ 9231109/ Contract research/City University of Hong Kong


Service (to design, supply and install at Hong Kong, Macau, China, Europe, UK, etc):


  • advise the design of a wetland system (with an automatic programmable control panel) during the design stage and tender stage
  • design the wetland system, including but not limited to grey water pre-treatment system, species selection, soil properties, hydrology and flow pattern of wetland, loading issue etc.
  • design,  installation,  commissioning,  operation  and maintenance  of  grey  water  reuse  and  rainwater  harvesting  systems,  safety precautions, education  and  training  requirements for end-users  as  well  as  operators  and  maintenance staff


Inquiry: Please contact k.hui@uea.ac.uk for more information and quotation.


Related information:


Related keywords: BEAM Plus Platinum certification; LEED Platinum by the United States Green Building Council; mitigation of heat island effect; sustainable built environment


Before construction: July 2013

Wetland zone 1 (WZ 1)

wetland zone 1a

WZ 2,3,4

wetland zone 2


After construction: 22 Feb 2014

WZ 1

wetland zone

WZ 1, 2, 3

wetland zone

WZ 2, 3, 4

wetland zone


Date: 4 Aug 2014

WZ 1

wetland zone

WZ 2, 3

wetland zone

WZ 4

wetland zone

Effectiveness of Installing Musical Staircases at CityU (Hong Kong) in Changing Behavior toward Environmental Sustainability


Project description:

We are pleased to introduce “musical stairs” into CityU to motivate and encourage students and staff to take the stairs instead of elevators or escalators.

“Musical stairs”, which was inspired by the fun theory project [1], aims to promote fitness awareness and to change the mindset of students and staff regarding energy conservation. Studies reveal that 66% more people chose to take the stairs instead of the adjacent escalator after the musical feature was installed [2]. A similar musical stairs project has also been introduced in Nanjing Subway in China [3]. Humans have the tendency to go with the flow. People tend to follow their peers by mimicking their actions [4]. If more people use the stairs, other people will follow suit.

The proposed project aims to add a simple and non-destructive musical device to ordinary stairs to provide users with entertainment, thus capturing their attention and offering a more enjoyable way of using stairs. Using stairs significantly helps in losing weight. This activity is an easy and practical alternative for busy people who don’t get enough regular exercise.

Inquiry: Please contact k.hui@uea.ac.uk for more information and quotation.


  1. O. Kommentarer, "Piano Staircase," 2009. Available from: http://www.thefuntheory.com/piano-staircase
  2. X. Zhu, "The fashion tour of musical stairs," 2012. Available from: http://www.thefuntheory.com/piano-staircase
  3. Starry Story, "The fashion tour of musical stairs"
  4. P.G. Hansen, Enlightenment blind spots, 2011.

Inquiry: Please contact us for more information.


musical stairs