tic acid 27 ml L -1 , surface agent 20-30 mg L -1 , IF-MoS 2 and 2H-MoS 2 3 g L -1 , pH=4.8-5.1, temperature at 353-358 K and the depositing time is 2 h. The electroless coatings were treated at 673 K for 2 h in vacuum. The surface morphology of the coatings was characterized by scanning electron microscopy (SEM, FSEM SIRION JY/ T010-1996).The tribological properties of the coatings were investigated using a pin-ondisk wear tester (MMW-1) under unlubricated condition in air (relative humidity 60 %) at sliding speed of 0.126 m s -1 . The spherical pins with radius of 5 mm were fabricated by quenched-and-tempered medium carbon steel with a hardness of HB220. The test loads ranged from 50 to 120 M. Friction coefficient were calculated by dividing the friction force that was recorded on line via torque as measured by the strain gauge. Mass loss was measured with an analytical balance at an interval of 5 min throughout the test. The worn surfaces of the electroless coatings were observed also by scanning electron microscopy (SEM, FSEM SIRION JY/T010-1996).

New ordered mesoporous carbide derived carbon materials with extraordinary high specific surface areas up to ∼2800 m 2 g -1 were synthesized by selective extraction of silicon from ordered mesoporous silicon carbide. Although the degree of mesostructure ordering is lower than that of the CMK-type materials they exhibit higher specific surface areas and high protein adsorption capacities. We show that they can be effectively functionalized with sulfonic groups and become excellent solid acid catalysts for processing large organic molecules.

Ordered mesoporous SiC with high specific surface area (650-800 m(2) g(-1)) and well ordered pore structure was obtained via nanocasting of polycarbosilanes into SBA-15 and subsequent conversion of the polymer at 1300 degrees C.

Silicon carbide (SiC) was infiltrated into the ordered mesoporous molecular sieves MCM-48 and SBA-15 using chemical vapor infiltration (CVI) of dimethyldichlorosilane (DDS) and hydrogen as the carrier gas. The infiltration process was followed ex situ using nitrogen physisorption measurements, small- and wide-angle X-ray diffraction, X-ray photoelectron spectroscopy, IR spectroscopy, and transmission electron microscopy. For MCM-48, infiltration at lower temperatures (1023 K) affords a thin, X-ray amorphous, SiC-based coating on the inner surface of the molecular sieve and the pore size of the mesoporous host decreases from 2.4 nm into the micropore regime (<2 nm). At higher temperature (1163 K), the deposition of 20−30-nm sized β-SiC particles is observed on the outer surface of the mesoporous particles as a process competitive to the pore filling. The crystalline nanoparticles form a hard protective coating on the outer surface of the larger spherical MCM-48 particles resembling hedgehog-like core−shell particles composed of an inner ordered mesoporous matrix and a hard nanosized silicon carbide coating. For SBA-15 it is shown that in the early stages of the CVI process at 1118 K, an ultrathin coating is produced that mainly consists of silicon oxycarbide. Subsequently, X-ray amorphous SiC is formed on top of this coating. In SBA-15, along with the formation of the coating, the pore size decreases from 5.5 to 3.0 nm, but further deposition leads to inhomogeneous coatings, and pore blocking and crystalline β-SiC particles are detected on the outer surface of the porous matrix by means of dark field transmission electron microscopy and wide-angle X-ray diffraction. The CVI process results in a significant enhancement of the thermal stability of SBA-15 even for very small degrees of filling.

Ordered mesoporous silicon carbide ceramics with hexagonal p6mm (OM-SiC-3, OM-SiC-5), cubic Ia3d (OM-SiC-8) and cubic I41/a or lower (OM-SiC-8) pore arrangement symmetries were prepared via nanocasting of SBA-15 and KIT-6 ordered mesoporous silica templates with polycarbosilane (PCS) precursor (numbering of the OM-SiC materials corresponds to their CMK ordered mesoporous carbon analogues). Four different PCS were used for the OM-SiC preparation (liquid SMP-10, low-molecular-weight PCS with M W = 800 melted at 320 °C and PCS with M W = 800, 1400, 3500 dissolved in heptane/butanol). Infiltration of liquid vinyl functionalized SMP-10 precursor, and subsequent pyrolysis in vacuum resulted in OM-SiC-5 materials with tubular structure similar to that of the CMK-5 carbons (according to the TEM, low angle X-ray diffraction and nitrogen physisorption measurements). No significant differences were observed between the direct melt (PCS-800 at 320 °C) and wet impregnation procedure (PCS-800 in heptane/butanol) for OM-SiC-3, whereas significant differences were measured for materials prepared using different molecular weights of the PCS precursors. The influence of different precursor loadings and final pyrolysis temperature was also investigated. In the case of materials prepared from cubic KIT-6, transformation of the OM-SiC-8 symmetry could be observed by small-angle X-ray diffraction.