A three-dimensional, mesoporous, silicate containing zirconium, Zr-TUD-1, was synthesized by a direct hydrothermal treatment method with triethanolamine as a complexing and templating reagent to ensure that zirconium was incorporated as isolated atoms. The mesoporosity of Zr-TUD-1 was confirmed by X-ray diffraction (XRD), N(2) sorption and high-resolution transmission electron micrograph (HR-TEM) studies. The nature and strength of the Lewis acid sites present in Zr-TUD-1 were evaluated by FTIR studies of pyridine adsorption and temperature-programmed desorption of ammonia. FTIR, X-ray photoelectron spectroscopic (XPS) and UV/Vis spectroscopic studies showed that, at Si/Zr ratios of 25 and higher, all the zirconium was tetrahedrally incorporated into the mesoporous framework, while at low Si/Zr ratios, a small part of the zirconium was present as ZrO(2) nanoparticles. Zr-TUD-1 is a Lewis acidic, stable and recyclable catalyst for the Meerwein-Ponndorf-Verley (MPV) reaction and for the Prins reaction.

Porosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer–Emmett–Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of micro‐ and mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already‐measured raw adsorption isotherms were provided to sixty‐one labs, who were asked to calculate the corresponding BET areas. This round‐robin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called “BET surface identification” (BETSI), expands on the well‐known Rouquerol criteria and makes an unambiguous BET area assignment possible.

Mesoporous TUD-1 and M-TUD-1 are straightforward to prepare via an environmentally benign synthesis. The resulting materials are excellent catalysts for oxidations, C–C bond forming reactions and photocatalysis. Furthermore the materials have shown potential for the slow release of drugs and as contrast agents.

Methanol synthesis by means of direct CO 2 hydrogenation has the potential to contribute to climate change mitigation by turning the most important greenhouse gas into a commodity. However, for this process to become industrially relevant, catalytic systems with improved activity, selectivity and stability are required. Here we explore the potential of metal-organic frameworks (MOF) as precursors for synthesis of Co 3 O 4 -supported In 2 O 3 oxide composites for the direct CO 2 hydrogenation to methanol. Stepwise pyrolytic-oxidative decomposition of indium-impregnated ZIF-67(Co) MOF affords the formation of a nanostructured In 2 O 3 @Co 3 O 4 reticulated shell composite material able to reach a maximum methanol production rate of 0.65 g MeOH •g cat -1 •h -1 with selectivity as high as 87% over 100 h on stream. Textural characteristics of the sacrificial ZIF-67(Co) matrix and In-loading were found to be important variables for optimizing the catalyst performance such as induction time, methanol productivity and selectivity. The structural investigation on the catalytic system reveals that the catalyst undergoes reorganization under reaction conditions, transforming from a Co 3 O 4 with amorphous In 2 O 3 shell into Co 3 InC 0.75 covered by a layer consisting of a mixture of amorphous CoO x and In 2 O 3 oxides. Structural reorganization is responsible for the observed induction period, while the amorphous mixed cobalt indium oxide shell is responsible for the high methanol yield and selectivity. Additionally, these results demonstrate the tunable performance of MOF-derived In 2 O 3 @Co 3 O 4 catalyst as a function of the reaction conditions which allows to establish a reasonable trade-off between high methanol yield and selectivity in a wide temperature and pressure window.

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