The comparative catalytic activity and coke resistance are examined in carbon dioxide reforming of methane over Ni/CeO 2 nanorods (NR) and nanopolyhedra (NP). The Ni/CeO 2 −NR catalysts display more excellent catalytic activity and higher coke resistance compared with the Ni/CeO 2 −NP. The high resolution transmission electron microscope reveals that the predominantly exposed planes are the unusually reactive {110} and {100} planes on the CeO 2 − NR rather than the stable {111} one on the CeO 2 −NP. The prepared samples were also characterized by X-ray diffraction, transmission electron microscopy, hydrogen temperature-programmed reduction, X-ray photoelectron spectroscopy, UV and visible Raman spectra, and oxygen temperature-programmed oxidation. The {110} and {100} planes show great superiority for the anchoring of Ni nanoparticles, which results in the existence of strong metal−support interaction effect (SMSI). The SMSI effect can be helpful to prevent sintering of Ni particles, which benefits to reduce the deactivation of catalytic activity. Besides, the oxygen vacancies and the mobility of lattice oxygen also show the morphology dependence. They can participate into the catalytic reaction and be beneficial to the activation of carbon deposition. In conclusion, the excellent catalytic activity and coke resistance of the Ni/CeO 2 −NR should be attributed to the SMSI effect and abundant oxygen vacancies.

In order to obtain excellent desalination behavior during the capacitive deionization (CDI) process, electrodes should provide efficient pathways for ion and electron transport. Here we open up a new opportunity to prepare high performance capacitive deionization (CDI) electrodes based on threedimensional macroporous graphene architectures (3DMGA). The 3DMGA were fabricated by a simple template-directed method using polystyrene microspheres as sacrificial templates. The resulting 3DMGA exhibited a 3D interconnected structure with large specific surface area and high electric conductivity.The electrochemical behavior of the 3DMGA electrodes was analyzed by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. It was found that the 3DMGA showed superiority in electrosorption capacitance, low inner resistance, high reversibility and excellent stability. The power and energy density analysis further demonstrated that the 3DMGA electrode had a higher power output and lower energy consumption. According to the electrochemical measurements, the 3DMGA is quite desirable for high performance and low energy consumption capacitive deionization. The desalination capacity was evaluated by a batch mode electrosorptive experiment in a NaCl aqueous solution. An excellent desalination behavior of the 3DMGA was obtained due to the large accessible surface area, high electric conductivity and unique 3D interconnected macroporous structure. The 3DMGA was confirmed to be a promising material for CDI application.

Capacitive deionization (CDI) with low-energy consumption and no secondary waste is emerging as a novel desalination technology. Graphene/mesoporous carbon (GE/MC) composites have been prepared via a direct triblock-copolymer-templating method and used as CDI electrodes for the first time. The influences of GE content on the textural properties and electrochemical performance were studied. The transmission electron microscopy and nitrogen adsorption-desorption analysis indicate that mesoporous structures are well retained and the composites display improved specific surface area and pore size distribution, as well as pore volume. Well dispersed GE nanosheets are deduced to be beneficial for enhanced electrical conductivity. The electrochemical performance of electrodes in an NaCl aqueous solution was characterized by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy measurements. The composite electrodes perform better on the capacitance values, conductive behaviour, rate performance and cyclic stability. The desalination capacity of the electrodes was evaluated by a batch mode electrosorptive experiment and the amount of adsorbed ions can reach 731 μg g⁻¹ for the GE/MC composite electrode with a GE content of 5 wt%, which is much higher than that of MC alone (590 μg g⁻¹). The enhanced CDI performance of the composite electrodes can be attributed to the better conductive behaviour and higher specific surface area.

A three-dimensional graphene-based hierarchically porous carbon (3DGHPC) has been prepared by a dualtemplate strategy and explored as the electrode for capacitive deionization (CDI). The texture analyses indicate that the incorporation of porous carbon into the three-dimensional graphene (3DG) has constructed a hierarchical pore network with a bimodal pore distribution. Compared to those of the 3DG (250.3 m 2 g À1 , 0.49 cm 3 g À1 ), the 3DGHPC exhibits a higher specific surface area of 384.4 m 2 g À1 and an improved pore volume of 0.73 cm 3 g À1 . The electrosorption behavior investigated by electrochemical techniques demonstrates that the 3DGHPC electrode displays superiority in specific capacitance and cyclability, as well as electrical conductivity. The CDI performance evaluated by batch mode experiments at a direct voltage of 1.2 V in a 25 mg L À1 NaCl aqueous solution reveals that the 3DGHPC electrode presents a higher electrosorptive capacity of 6.18 mg g À1 and an increased desalination efficiency of 88.96%. The enhanced deionization properties are deduced to arise from the improved specific surface area and increased pore volume, as well as an elevated electrical conductivity. † Electronic supplementary information (ESI) available: Details of texture characterizations and electrochemical measurements for prepared materials, SEM and TEM images of the GO/SiO 2 composite, the typical CV and Nyquist plots of PC electrode were presented. See

The morphology effect of ZrO 2 −CeO 2 on the performance of MnO x /ZrO 2 −CeO 2 catalyst for the selective catalytic reduction of NO with ammonia was investigated. The catalytic tests showed that the MnO x /ZrO 2 −CeO 2 nanorods achieved significantly higher NO conversions than the nanocubes and nanopolyhedra. The catalytic tests also showed that the MnO x /ZrO 2 −CeO 2 nanorods achieved a significantly higher rate constant with respect to NO conversion than that of the nanocubes and nanopolyhedra. On the nanorods, the apparent activation energy is 25 kJ mol −1 , which was much lower than the values of nanocubes and nanopolyhedra (42 and 43 kJ mol −1 ). The high resolution transmission electron microscopy showed that the nanorods predominately exposed {110} and {100} planes. It was demonstrated that the ZrO 2 −CeO 2 nanorods had a strong interaction with MnO x species, which resulted in great superiority for the selective catalytic reduction of NO. The excellent catalytic activity of the MnO x /ZrO 2 −CeO 2 nanorods should be attributed to the Mn 4+ species, adsorbed surface oxygen and oxygen vacancies which are associated with their exposed {110} and {100} planes.

Monolithic catalysts derived from in situ supported hydrotalcite-like films on Al wires display high resistance to coke formation and sintering in the dry reforming of methane due to their hierarchical porous structure, well dispersed metallic nickel species, more basic sites and strong metal-support interaction effect.

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