Doped Framework Iron Hydroxyl Phosphate as Photocatalyst for Hydrogen Production from Water/Methanol Mixtures

[EN] In the search for novel photocatalysts for hydrogen production and with the alpha-Fe2O3 photoelectrocatalyst as a recent precedent, we report herein the preparation, semiconductor properties and photocatalytic activity of metal-doped (0.1-5 wt.-% loading) iron hydroxyl phosphate (FeP). X-ray diffraction analyses of FeP samples subjected to extended photocatalytic irradiation showed the stability of this framework phosphate under photocatalytic conditions. Doping increased the photocatalytic efficiency of FeP for all dopants, with the optimal doping level between 0.1 and 1%. Under the optimized conditions (Cr at 1% doping), the photocatalytic activity of FeP reached a hydrogen production rate of 35.82 mu molg(Fe)(-1) in the absence of platinum as co-catalyst. The conduction flat band potential was estimated by photocurrent measurements or impedance spectroscopy to be 0.1 eV versus NHE and the charge carrier density 2.6 x 10(20) carriers cm(-3). Transient absorption spectroscopy revealed a transient species decaying on the microsecond time-scale characterized by a broad band spanning 300-750 nm. This transient was attributed to the charge-separated state. These results are promising for the development of novel photocatalytic materials based on framework metal phosphate.Financial support by the Spanish Ministry of Economy and Competitiveness (MEC) (Severo Ochoa and CTQ20212-32315) and the Generalidad Valenciana (Prometeo 2012/014) is gratefully acknowledged. M. S. thanks the Spanish Consejo Superior de Investigaciones Cientificas (CSIC) and Technical University of Valencia for a postgraduate scholarship.Serra, M.; García Baldoví, H.; Alvaro Rodríguez, MM.; García Gómez, H. (2015). Doped Framework Iron Hydroxyl Phosphate as Photocatalyst for Hydrogen Production from Water/Methanol Mixtures. European Journal of Inorganic Chemistry. 2015(25):4237-4243. https://doi.org/10.1002/ejic.201500629S42374243201525Amao, Y. (2011). 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Exploring excited states of Pt(ii) diimine catecholates for photoinduced charge separation

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Xanthan-Based Hydrogel for Stable and Efficient Quasi-Solid Truly Aqueous Dye-Sensitized Solar Cell with Cobalt Mediator

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(3aR*,5R*)-5-(4-Chloro­phen­yl)-1,2,3,3a-tetra­hydro­benzo[e]pyrrolo­[2,1-b][1,3]ox­azepin-10(5H)-one

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