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To improve the stability of molybdenum carbide catalysts in dimethyl ether steam reforming (DSR), the inactivation mechanism and the performance of Pt modified catalyst has been investigated. The Mo2C oxidation induced by H2O is verified to be the main reason of catalytic deactivation. After modified with Pt, the H2 production rate and selectivity are greatly enhanced, reaches 1605 μmol min−1·gcat−1 at 350 °C, in comparison to that of the Mo2C/Al2O3 catalyst. Moreover, the 2%Pt–Mo2C/Al2O3 catalyst is more stable with only 20% activity loss after 50 h on stream compares to the 73% activity loss in 12 h with Mo2C/Al2O3 catalyst. By means of in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), the enhancement brought by Pt is ascribed to the consumption acceleration of intermediate oxygen species on catalyst surface and the decline of onset temperature of DSR reaction. It is expected that these findings can lead us to more practical molybdenum carbide catalysts in DSR.

To fabricate effective and stable OER electrode in water electrolysis, self-doped TiO2 nanotube arrays which has a higher electrical conductivity than pristine TiO2 nanotube arrays was used as the support for loading IrO2. The self-doped TNTA was fabricated by a simple electrochemical reduction of TNTA in neutral electrolyte solution, and then IrO2 nano particles were deposited by pulse electro-deposition method. The cyclic voltammetric behavior, electrical conductivity and micro structure of self-doped TNTA prepared at different reduction potential were characterized to obtain an optimal performance, and self-doped TNTA prepared under −1.9 V (vs. Ag/AgCl) shows the best electrochemical performance. After depositing IrO2, the OER activity and stability of new electrodes were also determined. Due to the enhanced electrical conductivity of support, the mass activity of IrO2/self-doped TNTA are 50 times higher than IrO2/TNTA. The OER stability of new electrode was evaluated under constant current of 5 mA/cm2, IrO2/TNTA and IrO2/Ti were also tested for comparison. A higher stability of IrO2/self-doped TNTA electrode is observed than the other two electrodes, and XPS studies indicate a lower oxidation state of Ir in IrO2/self-doped TNTA, this shows a possible interactions between IrO2 and the new support.

Porous silica coated Ni/CeO 2 ZrO 2 catalysts were synthesized for steam reforming of acetic acid. The silica coated Ni/CeO 2 ZrO 2 catalyst showed a significantly enhanced activity (95% acetic acid conversion) than the Ni/CeO 2 ZrO 2 catalysts (62% acetic acid conversion) at a low temperature (550 °C). Interaction between Ni/CeO 2 ZrO 2 and silica layer was proved to be a crucial role on enhancing of catalytic activities. Further characterization (XPS, H 2 -TPR) indicates this interaction facilitates the steam reforming reaction and raises the selectivity of CO by modifying the surface Ni electronic structure. In addition, the coated catalyst also exhibited a good stability and no obvious deactivation was detected at 550 °C and 600 °C within 30 h.

IrO2 was electro-deposited on hydrogenated TiO2 nanotube arrays (TNTA) to form IrO2/H-TNTA for oxygen evolution reaction (OER). Hydrogenation by calcining in H2 atmosphere was conducted to improve the electric conductivity, which was owing to partially reduce of Ti4+ in TNTA. It was found that hydrogenated TiO2 can facilitate the electro-deposition of IrO2, and elevate the OER activity compared to that of non-calcined and air-calcined TNTA, which would be due to the improved conductivity of H-TNTA. IrO2/H-TNTA shows a five-fold higher activity than IrO2/air-TNTA with the same loading amount. The coverage of IrO2 on the surface of hydrogenated TNTA is crucial to the stability of catalyst and with the increased loading amount of IrO2, IrO2/H-TNTA shows much higher stability.

A series of Ni-based catalysts supported on Ce–Zr–O were synthesized via impregnation and applied in the reverse water gas shift reaction (RWGS). BET, XRD, TPR, SEM, TEM and XPS were employed as the characterization of catalysts. Catalytic activities of Ni/Ce–Zr–O with different Ni contents were evaluated in RWGS under atmospheric pressure and at the temperature range of 550–750 °C in a fixed-bed quartz reactor. CO2 conversion reaches 49.66% and maintains stable after 80 h of reaction over 3 wt% Ni/Ce–Zr–O. CO selectivity can reach 99.65% for the catalyst with 10 wt% Ni at 750 °C. The Ni/Ce–Zr–O catalyst provides high activity, stability and selectivity in the conversion of CO2 to CO at high temperature. Ce–Zr–O solid solution is formed by co-precipitation and Ni is able to be incorporated into the Ce–Zr–O lattice via impregnation. The Ni species on catalyst surface can be considered as the active site for RWGS.