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A high-deposition-area, robust inorganic scaffold, unique in its reproducible anisotropic macropores, is reported. This scaffold has a Young’s modulus of 455 ± 34 kPa and a yield strength of 215 ± 10 kPa in compression. It supports 3.5 ± 1.0 mL min−1 cm−2 volumetric flux of water with a modest 4.4 kPa head pressure. The scaffold is generated by freeze-casting a low-pH, concentrated silicic acid solution, followed by supercritical drying (SCD), changing the way water glass is used to generate support substrates. The scaffold enables facile immobilization of molecules or nanoparticles for liquid-phase applications, including heterogeneous catalysis, separations, biomedical devices, and energy storage. 

An often-quoted statement attributed to Wolfgang Pauli is that God made the bulk, but the surface was invented by the devil. Although humorous, the statement really reflects frustration in developing a detailed picture of a surface. In the last several decades, that frustration has begun to abate with numerous techniques providing clues to interactions and reactions at surfaces. Often these techniques require considerable prior knowledge. Complex mixtures on irregular or soft surfaces—complex interfaces—thus represent the last frontier. Two optical techniques: sum frequency generation (SFG) and second harmonic generation (SHG) are beginning to lift the veil on complex interfaces. Of these techniques, SFG with one excitation in the infrared has the potential to provide exquisite molecular- and moiety-specific vibrational data. This Perspective is intended both to aid newcomers in gaining traction in this field and to demonstrate the impact of high-phase resolution. It starts with a basic description of light-induced surface polarization that is at the heart of SFG. The sum frequency is generated when the input fields are sufficiently intense that the interaction is nonlinear. This nonlinearity represents a challenge for disentangling data to reveal the molecular-level picture. Three, high-phase-resolution methods that reveal interactions at the surface are described.