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The discovery in the late 1990s of ordered, high surface area silicas with pore sizes of 5 nm and above opened the way to the study of well-defined biomolecule-mesoporous silica hybrids. In particular, it has been possible to immobilize a range of small to medium size enzymes, such as proteases, lipases and peroxidases, via physisorption, encapsulation and tethering on the internal surfaces of the solids. Use has also been made of silicas functionalized for this purpose. In many cases the immobilized enzymes are both active and re-usable. Here we review the studies on enzymes immobilized on ordered mesoporous solids and assess the need for careful studies in real applications. Furthermore, we note the emerging applications of related biomolecule-mesoporous solid hybrids in other applications, such as intracellular drug delivery and transfection technology.

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Enzymatic reduction using oxidoreductases is important in commercial chemical production. This enzymatic action requires a cofactor (e.g., NADH) as a hydrogen source that is consumed during reaction and must be regenerated. We present, for the first time, an in situ NADH regeneration (NAD + → NADH) using a heterogeneous catalyst (Pt/Al 2 O 3 ) and H 2 coupled with an enzymatic reduction. This regeneration system can be operated at ambient pressure where NADH yield and turnover frequency (TOF) increased with temperature (20−37 °C) and pH (4.0−9.9) delivering full selectivity to enzymatically active NADH. Cofactor regeneration by heterogeneous catalysis represents a cleaner (H + as sole byproduct) alternative to current enzymatic and homogeneous (electro-and photo-) catalytic methods with the added benefit of facile catalyst separation. The viability of coupling cofactor regeneration with enzymatic (alcohol dehydrogenase, ADH) reaction is established in aldehyde reduction (propanal to propanol) where 100% alcohol yield was achieved. The potential of this hybrid inorganic−enzymatic system is further demonstrated in the continuous (fed-batch) conversion of propanal with catalyst (activity/selectivity) stability for up to 100 h.

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Carbon capture and storage (CCS) technologies aiming at tackling CO2 emission have attracted much attention from scientists of various backgrounds. Most CCS systems require an efficient adsorbent to remove CO2 from sources such as fossil fuels (pre‐combustion) or flue gas from power generation (post‐combustion). Research on developing efficient adsorbents with a substantial capacity, good stability and recyclability has grown rapidly in the past decade. Because of their high surface area, highly porous structure, and high stability, various nanoporous materials have been viewed as good candidates for this challenging task. Here, recent developments in several classes of nanoporous materials, such as zeolites, metal organic frameworks (MOFs), mesoporous silicas, carbon nanotubes, and organic cage frameworks, for CCS are examined and potential future directions for CCS technology are discussed. The main criteria for a sustainable CO2 adsorbent for industrial use are also rationalized. Moreover, catalytic transformations of CO2 to other chemical species using nanoporous catalysts and their potential for large scale carbon capture and utilization (CCU) processes are also discussed. Application of CCU technologies avoids any potential hazard associated with CO2 reservoirs and allows possible recovery of some running cost for CO2 capture by manufacturing valuable chemicals.