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Fuel cell, as a promising future energy device, is one of the potential electric generators maintaining the sustainable development of our society and alleviating the major problems related to the energy shortage and environment pollution. However, the high cost and the limited resource of Pt remain the key obstacles for the commercialization of fuel cells. A hybrid dual-template strategy is developed to synthesize the nitrogen-doped ordered hierarchically porous carbon (NHMC) via a surfactant-templating organic resol self-assembly with F127 as soft template and SiO2 nanosphere as the hard-template. The NHMC catalyst presents three-dimensional hierarchically porous structure, composed of small ordered mesopore (∼3.8 nm), large 3-D interconnected mesopore (∼12 nm) as well as micropore. The catalyst exhibits tailored pore structures and a well-tuned surface chemical environment. It displays high onset potential of 0.91 V and half-wave potential of 0.76 V as well as high limiting current via four-electron pathway for oxygen reduction reaction (ORR). The NHMC also shows high stability and excellent methanol tolerance. This work brings inspiration for the synthesis of low-cos Pt-free catalyst with high activity, stability as well as high methanol tolerance.

The conversion of carbon dioxide to chemicals by the electrochemical reactions (ERC) is an efficient solution to the current energy crisis and excess CO2 emissions. It is still a great challenge and of significance to synthesize a highly selective, efficient, and non−noble metal electrocatalyst that facilitates the ERC reaction. A novel triton X−100 (C14H22O(C2H4O)n) assisted electrodeposition method was developed to synthesize the ordered cone−structured tin (OCSn) electrocatalysts with controllable morphology and structure. The results suggest that Triton X−100 plays an important role in directing the structure of the Sn electrocatalysts during the electrodeposition process. The OCSn synthesized at 60 mA cm−2 achieves the best performances. It selectively catalyzes the ERC on the onset potential about 110 mV lower than Sn synthesized without Triton X−100. In 0.5 M NaHCO3, high faradaic efficiency (92%) for formate product on OCSn has been achieved. More prominently, the catalyst presents excellent stability, showing no performance deterioration during 30 h electrolysis. This work provides an efficient, green, and scalable synthesis method of the electrocatalyst for CO2 reduction to formate.

A compact reactor for natural gas steam reforming, in which hydrogen production was coupled with an internal combustor in alternate chambers, was developed and tested. Based on the target heat tran...

NiO/CexZryO2-Sil-1 catalysts were prepared using an In-Situ self-assembly approach by coupling silicalite-1 and CexZryO2. This one-step synthesis method utilized the high surface area and hydrothermal stability of silicalite-1 and the good oxidation-reduction ability of the CexZryO2, and hence offered high synthesis efficiency. The catalyst structure was examined by N2-physisorption, temperature-programmed reduction, transmission electron microscopy, and X-ray diffraction. All the results showed that silicalite-1 was well-encapsulated by NiO/Ce0.5Zr0.5O2. Furthermore, the effect of the Ce/Zr molar ratio on the performance of the catalysts was investigated in detail. The catalysts were subjected to methane steam reforming at high temperatures to evaluate their catalytic performance. The result showed that the NiO/Ce0.5Zr0.5O2-Sil-1 catalyst exhibited the best performance and its methane conversion efficiency reached up to 99.5%. Even after 16 h of continuous stability test, this catalyst could retain a methane conversion efficiency of 97.8%.

NiO/M-Sil-1 catalysts were successfully prepared by in situ coupled assembly of metal oxides and silicalite-1 zeolite. All the NiO/M-Sil-1 samples had high surface areas, which resulted from the uniform dispersion and small particle size of the active components. Zr-doped Ni/M-Sil-1 exhibited a 20% lower NiO average particle size and a 6% lower NiO reduction temperature compared with those of the nondoped catalysts. Consequently, the Ni/Zr-Sil-1 catalyst exhibited the best catalytic performance, with the CO selectivity in methane steam reforming drastically decreasing by 11.5%, H₂ concentration in the reformed gas increasing by about 1.7%, and H₂/CO molar ratio increasing by 0.8. Moreover, its initial methane conversion efficiency was 99.8% and was retained by 97.7% after a 578 h continuous stability test. Furthermore, the traditional water/carbon molar ratio in methane steam reforming reduced from 3-5 to 2, and the methane conversion remained above 98.1%, with a high thermal stability that substantially increased the energy efficiency.

The series of Ce0.5Zr0.5O2 and MOx-Ce0.5Zr0.5O2 supports were synthesized by a micro-emulsion method. This method efficiently controlled the average particle size of supports below 6 nm. The supported NiO/Ce0.5Zr0.5O2 and NiO/MOx-Ce0.5Zr0.5O2 catalysts were prepared by an incipient-wetness impregnation method. The OCS measurement and TPR result showed that adding Mg improved obviously the OSC of supports and the interaction between active components and supports. Furthermore, 8 wt%NiO/4wt%MgO-Ce0.5Zr0.5O2 exhibited the highest catalytic performance. Its methane conversion reached up to 96% and enhanced 9% after 5 h compared to 8 wt%NiO/Ce0.5Zr0.5O2. Especially, Its methane conversion was above 97% after 50 h continuous test at 800 °C.

The series of MCM-41 and NiO/MCM-41 for steam reforming of methane were prepared by hydrothermal and impregnation techniques. Then, samples were characterized by XRD, BET, TPR, SEM and TEM methods. The results showed that the rod-shaped MCM-41 had the best performance in the hydrogen production due to it had high crystallinity and strong interaction with the nickel metal ion. Furthermore, the results indicated that the different content of nickel on MCM-41 had various dissimilar dispersion and particle size. This work proved that the 15 %NiO/MCM-41 had uniform nickel particle size distribution, the highest activity and stability in methane steam reforming.