Herein a novel synthetic route is described for the production of thermally stable, structurally well‐defined two‐dimensional (2D) hexagonal mesoporous nanocrystalline anatase (meso‐nc‐TiO2), with a large pore diameter, narrow pore‐size distribution, high surface area, and robust inorganic walls comprised of nanocrystalline anatase. The synthetic approach involves the evaporation‐induced co‐assembly of a non‐ionic amphiphilic triblock‐copolymer template and titanium tetraethoxide, but with a pivotal change in the main solvent of the system, where the commonly used ethanol is replaced with 1‐butanol. This seemingly minor modification in solvent type from ethanol to 1‐butanol turns out to be the key synthetic strategy for achieving a robust, structurally well‐ordered meso‐nc‐TiO2 material in the form of either thick or thin films. The beneficial “solvent” effect originates from the higher hydrophobicity of 1‐butanol than ethanol, enhancing microphase separation and templating, lower critical micelle concentration of the template in 1‐butanol, and the ability to increase the relative concentration of the inorganic precursor to template in the co‐assembly synthesis. Moreover, thin films with dimensions of several centimeters that are devoid of cracks down to the length scale of the mesostructure itself, having high porosity, well‐defined mesostructural features, and semi‐crystalline pore walls were straightforwardly and reproducibly obtained as a result of the physicochemical property advantages of 1‐butanol over ethanol within our synthesis scheme.

Herein we report a novel self-assembly synthesis, structural and optical characterization of mesoporous Bragg stacks (MBS) composed of spin-coated multilayer stacks of mesoporous TiO(2) and mesoporous SiO(2). Investigation of the optical response of MBS to the infiltration of alcohols and alkanes into its pores reveals better sensitivity and selectivity than conventional Bragg reflectors. Furthermore, we demonstrate that the chemical sensing ability can be tuned via layer thickness, composition and surface properties.

The mixed transition metal layered compound, LiNi 0.4 Mn 0.4 Co 0.2 O 2 , with the a-NaFeO 2 layer structure has been synthesized and characterized. The optimum temperature of synthesis was found to be 800-900 uC. Rietveld refinement showed that cobalt suppresses transition metal ion migration into the Li sites whereas nickel promotes the migration. XPS analysis shows that the Co and about 20% of the Ni and Mn are in the 31 oxidation state, while 80% of the Ni and Mn are in the 21 and 41 oxidation states, respectively. LiNi 0.4 Mn 0.4 Co 0.2 O 2 shows Curie-Weiss paramagnetic behavior above 150 K, and the value of the Curie constant is consistent with the above oxidation states. In lithium electrochemical cells the composition LiNi 0.4 Mn 0.4 Co 0.2 O 2 gave the highest reversible capacity among the studied compositions. It shows excellent rate capability, giving reversible capacities ranging from 180 to 155 mA h g 21 at current densities from 0.1 to 2.0 mA cm 22 . 2 1 4 J . M a t e r . C h e m . , 2 0 0 4 , 1 4 , 2 1 4 -2 2 0 T h i s j o u r n a l i s ß T h e R o y a l S o c i e t y o f C h e m i s t r y 2 0 0 4 View Online 2 1 8 J . M a t e r . C h e m . , 2 0 0 4 , 1 4 , 2 1 4 -2 2 0

A new class of mesoporous (nickel/platinum)-yttria-zirconia materials, denoted meso-(Ni/Pt)YZ, which may have utility as electrode material in solid oxide fuel cells (SOFCs), have been synthesized by aqueous co-assembly of glycometalates and metal complexes with a surfactant template. These materials form as solid solutions with compositions that can be tuned over the range 12-56 atom % yttrium and 10-30 atom % nickel or 1-10 wt % platinum. The microstructure of the channel wall is nanocrystalline yttria-zirconia (YZ) and nickel/platinum is incorporated as metal oxide/metal clusters with diameters comparable to the size of the pores depending on the degree of loading of the metal precursor. Calcination in air of as-synthesized meso-(Ni/Pt)YZ materials causes the channel walls to crystallize and thicken as the imbibed organics are lost. It is the relatively thick, YZ nanocrystalline walls which are believed to be responsible for the impressive 800 °C thermal stability of meso-(Ni/Pt)YZ. This new class of binary and ternary mesoporous materials display the highest recorded surface area of any known form of (metal)-yttria-stabilized-zirconia. A narrow mesopore size distribution, nanocrystalline channel walls, and high thermal stability may lead to significant improvements in fuel/oxidant mass transport, oxide ion mobility, electronic conductivity, and charge transfer at the triplephase-boundary region of SOFC electrodes. It may also enable a reduction in the operating temperature of the SOFC.