Directory
Pr. Kazuhiro TAKANABE
| When |
Sep 08, 2016 à 02:00 PM |
|---|---|
| Where |
Grande salle cbp LR6 |
| Contact |
Tangui Lebahers |
Quantitative Understanding of Photocatalytic Water Splitting
Photocatalysis can achieve energetically uphill reactions utilizing photon energy.1-4 Efficient photocatalytic reaction can be achieved when all the steps of photophysical and electrocatalytic processes are effectively connected in sequence.1 The processes include photon absorption, exciton separation, carrier diffusion and transport, and electrocatalysis.1 Most of the relevant properties can be quantitatively and separately measurable, which then leads to deep understanding of semiconductor photocatalyst and interface at the catalyst on its surface. As a Ta3N5 photocatalyst as a model material, our recent studies aimed to measure/calculate absorption coefficient,5 carrier lifetime,5 dielectric properties,6 effective masses of electron and hole,7 and band positions.7,8 Combining the photocatalyst with efficient electrocatalyst, intimate interface between semiconductor and catalyst to achieve high quantum efficiency.9 Using all the quantitative values of these properties, we established a simplified guideline to give the first estimate whether the material is suitable for photocatalytic overall water splitting.10 To understand the intrinsic limitations of the system, we numerically simulated simplified two-dimensional photocatalytic models using classical semiconductor device equations. Furthermore, impact of decoration of photocatalyst surface with excellent electrocatalysts was investigated with kinetic analysis and spectroscopic techniques including time-resolved tera-hertz spectroscopy.11,12 The presentation discusses the strength of these property measurements, resultant simulations, its outcomes, and the consequences for photocatalytic solar-to-fuel conversions.
Reference:
[1] K. Takanabe, Top. Curr. Chem., 2016, 371, 73-103.
[2] T. Hisatomi, K. Takanabe, K. Domen, Catal. Lett., 2015, 145, 95-108.
[3] K. Takanabe, K. Domen, ChemCatChem, 2012, 4, 1485-1497.
[4] K. Takanabe, K. Domen, Green, 2011, 1, 313-322.
[5] A. Ziani, E. Nurlaela, D.S. Dhawale, D. Alves Silva, E. Alarousu, O.F. Mohammed, K. Takanabe, Phys. Chem. Chem. Phys., 2015, 17, 2670-2677.
[6] E. Nurlaela, M. Harb, S. Del Gobbo, M. Vashishta, K. Takanabe, J. Solid State Chem., 2015, 229, 219-227.
[7] M. Harb, P. Sautet, E. Nurlaela, P. Raybaud, L. Cavallo, K. Domen, J.-M. Basset, K. Takanabe, Phys. Chem. Chem. Phys., 2014, 16, 20548-20560.
[8] E. Nurlaela, S. Ould-Chikh, M. Harb, S. Del Gobbo, M. Aouine, E. Puzenat, P. Sautet, K. Domen, J.-M. Basset, K. Takanabe, Chem. Mater., 2014, 26, 4812-4825.
[9] E. Nurlaela, S. Ould-Chikh, I. Llorens, J.-L. Hazemann, K. Takanabe, Chem. Mater., 2015, 27, 5685-5694.
[10] A.T. Garcia-Esparza, K. Takanabe, J. Mater. Chem. A, 2016, 4, 2894-2908.
[11] E. Nurlaela, T. Shinagawa, M. Qureshi, D.S. Dhawale, K. Takanabe, ACS Catal., 2016, 6, 1713-1722.
[12] E. Nurlaela, H. Wang, T. Shinagawa, S. Flanagan, S. Ould-Chikh, Z. Mics, P. Sautet, T. Le Bahers, E. Canovas, M. Bonn, K. Takanabe, ACS Catal., 2016, 6, 4117-4126.