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A facile approach of solvent‐evaporation‐induced coating and self‐assembly is demonstrated for the mass preparation of ordered mesoporous carbon‐silica composite monoliths by using a polyether polyol‐based polyurethane (PU) foam as a sacrificial scaffold. The preparation is carried out using resol as a carbon precursor, tetraethyl orthosilicate (TEOS) as a silica source and Pluronic F127 triblock copolymer as a template. The PU foam with its macrostructure provides a large, 3D, interconnecting interface for evaporation‐induced coating of the phenolic resin‐silica block‐copolymer composites and self‐assembly of the mesostructure, and endows the composite monoliths with a diversity of macroporous architectures. Small‐angle X‐ray scattering, X‐ray diffraction and transmission electron microscopy results indicate that the obtained composite monoliths have an ordered mesostructure with 2D hexagonal symmetry (p6m) and good thermal stability. By simply changing the mass ratio of the resol to TEOS over a wide range (10–90%), a series of ordered, mesoporous composite foams with different compositions can be obtained. The composite monoliths with hierarchical macro/mesopores exhibit large pore volumes (0.3–0.8 cm3 g−1), uniform pore sizes (4.2–9.0 nm), and surface areas (230–610 m2 g−1). A formation process for the hierarchical porous composite monoliths on the struts of the PU foam through the evaporation‐induced coating and self‐assembly method is described in detail. This simple strategy performed on commercial PU foam is a good candidate for mass production of interface‐assembly materials.

A simple strategy for the synthesis of macro-mesoporous carbonaceous monolith materials has been demonstrated through an organic organic self-assembly at the interface of an organic scaffold such as polyurethane (PU) foam. Hierarchically porous carbonaceous monoliths with cubic (Im m) or hexagonal (p6mm) mesostructure were prepared through evaporation induced self-assembly of the mesostructure on the three-dimensional (3-D) interconnecting struts of the PU foam scaffold. The preparation was carried out by using phenol/formaldehyde resol as a carbon precursor, triblock copolymer F127 as a template for the mesostructure and PU foam as a sacrificial monolithic scaffold. Their hierarchical pore system was macroscopically fabricated with cable-like mesostructured carbonaceous struts. The carbonaceous monoliths exhibit macropores of diameter 100 450 μm, adjustable uniform mesopores (3.8 7.5 nm), high surface areas (200 870 m 2 /g), and large pore volumes (0.17 0.58) cm 3 /g. Compared with the corresponding evaporation induced self-assembly (EISA) process on a planar substrate, this facile process is a time-saving, labor-saving, space-saving, and highly effi cient pathway for mass production of ordered mesoporous materials.

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The formation mechanism of the cubic mesoporous carbon, FDU-16, synthesized by evaporation-induced self-assembly (EISA) was investigated at the molecular level by electron paramagnetic resonance (EPR) spectroscopic techniques. This material is synthesized using F127 pluronic block copolymer [poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (PEO106-PPO70-PEO106)] as a structure-directing agent (template) and phenolic resol as a carbon precursor. Using two spin probes derived from pluronics with PEO and PPO chains of different lengths that are designed to sense different regions of the system, we followed the evaporation and thermopolymerization stages of the synthesis in situ. To make such studies possible, we have used a polyurethane foam support, placed in the EPR tube, which allows for the efficient solvent evaporation as required for EISA. We focused on the evolution of the dynamics of the template and its interactions with the resol during the reaction. We observed that during the evaporation stage the resol is distributed throughout the entire PEO blocks, all the way to the PPO–PEO interface, interacting with them via H-bonds, thus hindering the local motion of the PEO chains. At the end of this stage there is no polarity gradient along the PEO blocks, as found for traditional F127 micelles in water or during the synthesis of silica materials, and the mesostructure is not well-defined. A polarity and a resol gradient developed during the thermopolymerization stage where the polymerizing resol is driven out to the outer region of the PEO corona. This produces a corona of resin-pluronic composite and a resol-free PPO core with high mobility of the PEO segments close to the PPO–PEO interface and restricted mobility in the composite corona. During this stage the final structure sets in.