Biography

Ph.D and Postdoctoral Opportunities

Self funding Ph.D Position: Organo-Polyoxometalate Derivatves: New Materials for Photonics and Optical Computing

To discuss self-funding PhD opportunities, or post-doctoral fellowship applications in other areas of my research programme, please get in touch.

Biography

Dr. Fielden completed his MSci in Chemistry at the University of Bristol in 2000, before moving to the University of Glasgow where he graduated with a Ph.D in 2005 under the supervision of Prof. Leroy Cronin. He then spent two years working with Prof. Paul Kögerler at Ames Laboratory (Iowa State University) on the self-assembly and properties of polyoxometalates (POMs) and chiral magnetic materials. In 2007 he took up a postdoctoral position with Dr. Benjamin Coe at the University of Manchester, investigating redox-switchable NLO chromophores, and in 2010 was awarded a Marie Curie International Outgoing Fellowship. This took him back across the Atlantic to the laboratory of Prof. Craig Hill at Emory University, where he worked on POM functionalized photoelectrodes and the excited state properties of transition metal substituted POMs. He joined the UEA as a lecturer in 2012, transferring his Marie Curie reintegration year from Glasgow.

John is interested in the synthesis and optical and photophysical properties of coordination compounds and clusters, particularly relating to solar energy conversion and non-linear optics. In particular, he aims to devise ways of efficiently exploiting the properties of POMs as catalysts and electron acceptors in light-driven chemistry. Current projects include synthesis of POM-containing electro-polymer photocathodes, investigation of metallo-organic POM hybrids as photosensitizers, and multi-component catalytic arrays based on tripodal ligand systems. He also plans to extend the fundamental coordination chemistry of multi-molybdenum and tungsten clusters, and develop supramolecular recognition strategies that can be used to control the self-assembly of functional POM-based nanostructures.

Click here to go to the Energy Materials Laboratory homepage.

Selected Publications

Elliot N. Glass, John Fielden, Zhuangqun Huang, Xu Xiang, Djamaladdin G. Musaev, Tianquan Lian and Craig L. Hill
Transition Metal Substitution Effects on Metal-to-Polyoxometalate Charge Transfer
Inorg. Chem. 201655, 4308-4319. DOI: 10.1021/acs.inorgchem.6b00060

Ahmed Al-Yasari, Nick Van Steerteghem, Hani El Moll, Koen Clays and John Fielden.
Donor-Acceptor Organo-Imido Polyoxometalates: High Transparency, High Activity Redox-Active NLO Chromophores
Dalton. Trans. 201645, 2818-2822.
DOI:
 10.1039/C6DT00115G

John Fielden, Jordan M. Sumliner, Nannan Han, Yurii Gueletii, Xu Xiang, Djamaladdin G. Musaev, Tianquan Lian, and Craig L. Hill.
Water Splitting with Polyoxometalate-Treated Photoanodes: Enhancing Performance through Sensitizer Design
Chem. Sci. 20156, 5531-5543.
DOI:
10.1039/C5SC01439E

Elliot N. Glass, John Fielden, Alexey L. Kaledin, Djamaladdin G. Musaev, Tianquan Lian, and Craig L. Hill.
Extending Metal-to-Polyoxometalate Charge Transfer Lifetimes: The Effect of Heterometal Location
Chem. Eur. J. 201420, 4297–4307.
DOI:
10.1002/chem.201304119 

Xu Xiang, John Fielden, William E. Rodríguez-Córdoba, Zhuangqun Huang, Naifei Zhang, Zhen Luo, Djamaladdin G. Musaev, Tianquan Lian, and Craig L. Hill.Electron Transfer Dynamics in Semiconductor–Chromophore–Polyoxometalate Catalyst Photoanodes
J. Phys. Chem. C 2013117, 918–926.
DOI: 10.1021/jp312092u

B. J. Coe, J. Fielden, S. P. Foxon, J. A. Harris, M. Helliwell, B. S. Brunschwig, I. Asselberghs. K. Clays, J. Garín and J. Orduna.
Diquat Derivatives: Highly Active, Two Dimensional Nonlinear Optical Chromophores with Potential Redox-Switchability
J. Am. Chem. Soc. 2010, 132, 10498–10512.
DOI: 10.1021/ja103289a

Career History

  • 2012 – Lecturer in Energy Materials, UEA School of Chemistry
  • 2010 – 2013 Marie Curie International Outgoing Fellow, Emory University (Atlanta, USA) and UEA
  • 2007 – 2010 Post-Doctoral Research Associate, University of Manchester
  • 2005 – 2006 Post-Doctoral Research Associate, Ames Laboratory (US Department of Energy)
  • 2001 – 2004 Ph.D in Inorganic Chemistry, University of Glasgow
  • 1996 – 2000 MSci in Chemistry, University of Bristol

All Publications

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Al-Yasari, A., Van Steerteghem, N., El Moll, H., Clays, K., Fielden, J.

(2016)

Donor–acceptor organo-imido polyoxometalates: high transparency, high activity redox-active NLO chromophores,

in Dalton Transactions

45

(7)

pp. 2818-2822

Full Text UEA Repository

(Article)

(Published)


Glass, E., Fielden, J., Huang, Z., Xiang, X., Musaev, D., Lian, T., Hill, C.

(2016)

Transition Metal Substitution Effects on Metal-to-Polyoxometalate Charge Transfer,

in Inorganic Chemistry

55

(9)

pp. 4308-4319

Full Text UEA Repository

(Article)

(Published)


Fielden, J., Sumliner, J. M., Han, N., Geletii, Y., Xiang, X., Musaev, D. G., Lian, T., Hll, C. L.

(2015)

Water splitting with polyoxometalate-treated photoanodes: Enhancing performance through sensitizer design,

in Chemical Science

6

pp. 5531-5543

Full Text UEA Repository

(Article)

(Published)


Glass, E. N., Fielden, J., Kaledin, A. L., Musaev, D. G., Lian, T., Hill, C. L.

(2014)

Extending Metal-to-Polyoxometalate Charge Transfer Lifetimes: The Effect of Heterometal Location,

in Chemistry - A European Journal

20

(15)

pp. 4297-4307

Full Text UEA Repository

(Article)

(Published)


Tang, Y., He, W., Lu, Y., Fielden, J., Xiang, X., Yan, D.

(2014)

Assembly of ruthenium-based complex into metal-organic framework with tunable area-selected luminescence and enhanced photon-to-electron conversion efficiency,

in The Journal of Physical Chemistry C

118

(44)

article no. jp5092174

pp. 25365-25373

Full Text UEA Repository

(Article)

(Published)


Sumliner, J. M., Lv, H., Fielden, J., Geletii, Y. V., Hill, C. L.

(2014)

Polyoxometalate multi-electron-transfer catalytic systems for water splitting,

in European Journal of Inorganic Chemistry

2014

pp. 635-644

Full Text UEA Repository

(Article)

(Published)


Al-Yasari, A., Fielden, J.

(2014)

Polyoxometalates in visible-light photocatalysis and solar energy conversion,

in Reviews in Advanced Sciences and Engineering

3

(4)

article no. rase.2014.1077

pp. 304-319

Full Text UEA Repository

(Article)

(Published)


Xiang, X., Fielden, J., Rodríguez-Córdoba, W., Huang, Z., Zhang, N., Luo, Z., Musaev, D., Lian, T., Hill, C.

(2013)

Electron transfer dynamics in semiconductor–chromophore–polyoxometalate catalyst photoanodes,

in The Journal of Physical Chemistry C

117

(2)

pp. 918-926

Full Text UEA Repository

(Article)

(Published)


Fielden, J., Long, D., Speldrich, M., Kögerler, P., Cronin, L.

(2012)

[CoxCu1−x(DDOP)(OH2)(NO3)](NO3): hydrogen bond-driven distortion of cobalt(ii) by solid solution ‘network mismatch’,

in Dalton Transactions

41

(16)

pp. 4927-4934

Full Text UEA Repository

(Article)

(Published)


Fielden, J., Quasdorf, K., Cronin, L., Kögerler, P.

(2012)

A fluorophosphate-based inverse Keggin structure,

in Dalton Transactions

41

(33)

pp. 9876-9878

Full Text UEA Repository

(Article)

(Published)


Fielden, J., Speldrich, M., Besson, C., Kögerler, P.

(2012)

Chiral Hexanuclear Ferric Wheels,

in Inorganic Chemistry

51

(5)

pp. 2734-2736

Full Text UEA Repository

(Article)

(Published)


Tennant, D., Lake, B., James, A., Essler, F., Notbohm, S., Mikeska, H., Fielden, J., Kögerler, P., Canfield, P., Telling, M.

(2012)

Anomalous dynamical line shapes in a quantum magnet at finite temperature,

in Physical Review B

85

(1)

pp. 014402-014413

Full Text UEA Repository

(Article)

(Published)


Coe, B., Fielden, J., Foxon, S., Asselberghs, I., Clays, K., Van Cleuvenbergen, S., Brunschwig, B.

(2011)

Ferrocenyl Diquat Derivatives: Nonlinear Optical Activity, Multiple Redox States, and Unusual Reactivity,

in Organometallics

30

(21)

pp. 5731-5743

Full Text UEA Repository

(Article)

(Published)


Blackburn, O., Coe, B., Fielden, J., Helliwell, M., McDouall, J., Hutchings, M.

(2010)

Nickel(II) and Palladium(II) Complexes of Azobenzene-Containing Ligands as Dichroic Dyes,

in Inorganic Chemistry

49

(20)

pp. 9136-9150

Full Text UEA Repository

(Article)

(Published)


Clays, K., Docherty, R., Fielden, J., Helliwell, M., Raftery, J., Shaw, R., Swanson, C., Coe, B.

(2010)

Designing organic molecules for terahertz radiation generation in robust crystals,

Full Text UEA Repository

(Paper)

(Published)


Coe, B., Fielden, J., Foxon, S., Asselberghs, I., Clays, K., Brunschwig, B.

(2010)

Two-Dimensional, Pyrazine-Based Nonlinear Optical Chromophores with Ruthenium(II) Ammine Electron Donors,

in Inorganic Chemistry

49

(22)

pp. 10718-10726

Full Text UEA Repository

(Article)

(Published)


Coe, B., Fielden, J., Foxon, S., Brunschwig, B., Asselberghs, I., Clays, K., Samoc, A., Samoc, M.

(2010)

Combining Very Large Quadratic and Cubic Nonlinear Optical Responses in Extended, Tris-Chelate Metallochromophores with Six π-Conjugated Pyridinium Substituents,

in Journal of the American Chemical Society

132

(10)

pp. 3496-3513

Full Text UEA Repository

(Article)

(Published)


Coe, B., Fielden, J., Foxon, S., Harris, J., Helliwell, M., Brunschwig, B., Asselberghs, I., Clays, K., Garín, J., Orduna, J.

(2010)

Diquat Derivatives: Highly Active, Two-Dimensional Nonlinear Optical Chromophores with Potential Redox Switchability,

in Journal of the American Chemical Society

132

(30)

pp. 10498-10512

Full Text UEA Repository

(Article)

(Published)


Coe, B., Fielden, J., Foxon, S., Helliwell, M., Asselberghs, I., Clays, K., De Mey, K., Brunschwig, B.

(2010)

Syntheses and Properties of Two-Dimensional, Dicationic Nonlinear Optical Chromophores Based on Pyrazinyl Cores,

in The Journal of Organic Chemistry

75

(24)

pp. 8550-8563

Full Text UEA Repository

(Article)

(Published)


Coe, B., Fielden, J., Foxon, S., Helliwell, M., Brunschwig, B., Asselberghs, I., Clays, K., Olesiak, J., Matczyszyn, K., Samoc, M.

(2010)

Quadratic and Cubic Nonlinear Optical Properties of Salts of Diquat-Based Chromophores with Diphenylamino Substituents,

in The Journal of Physical Chemistry A

114

(45)

pp. 12028-12041

Full Text UEA Repository

(Article)

(Published)


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Key Research Interests

The Fielden group is currently working in the following areas:

  • Polyoxometalate-based non-linear optical chromophores and electropolymers. We have recently obtained a series of donor-acceptor chromophores based on polyoxometalates, including systems based on electropolymerizable pyrrole units.  The resulting materials are being tested as electrochemically controlled optical switches. 
  • Multi-component catalytic arrays: We are using small, heteroleptic tripodal ligands as a platform to build multifunctional arrays for small molecule activation.  The ligands can coordinate a transition metal in a bidentate or tetradentate coordination pocket, while providing a pendant group for introduction of proton or electron relays.  These will allow controlled study of secondary coordination sphere effects, and incorporation of redox active groups in the secondary sphere. 
  • POM-derivatives as photosensitizers: We are investigating the use of POMs as electron acceptor units in push-pull chromophores.  These are designed to improve the efficiency of p-type dye-sensitized solar cells by retarding recombination of photo-excited electrons to NiO, one of the major sources of inefficiencies in these systems.  
  • New p-type semiconductor nanomaterials: we are investigating replacement of NiO in the p-type DSSC, a key imperative to improve performance, in collaboration with Dr. Andrew Mayes.

Research Group Membership

The Fielden Group, February 2015

From left to right: Simon Child, John Fielden, Natalia Sanchez Moreno, David Miko, Phil Spence, Hani El-Moll, Ahmed Al-Yasari

From left to right: Simon Child, John Fielden, Natalia Sanchez Moreno, David Miko, Phil Spence, Hani El-Moll, Ahmed Al-Yasari

And among the Ziggurats...

Fielden group outside the UEA Ziggurat buildings

Fielden group outside the UEA Ziggurat buildings

 

 

External Activities and Indicators of Esteem

  • School Visit - Trent College, February 2016
  • Outreach - Norwich Science Cafe 2013 - Talk on Artificial Photosynthesis
  • Outreach - Photon Science Institute/Manchester Museum of Science and Industry 2010 - Meet the Photon Scientist
  • Outreach - University of Manchester 2009 - School Workshop - Non-Newtonian fluids

Administrative Posts

Module Organiser: Year 2 Inorganic Chemistry (CHE-5301B)

Chemistry Representative: Science Faculty Analytical Facilities User Group