The world is facing a climate emergency: unchecked pollution coupled with rising CO2 levels is putting unprecedented strain on the planet’s ecosystems. Technologies for environmental remediation are thus becoming increasingly...

As complex materials are widely used in emerging technologies for environmental and energy applications, it is important to be able to quantify their stimuli-response behaviors. Light is a useful stimulus to modulate multifunctional electrochemical, magnetic, optical, and structural properties in metal− organic frameworks (MOFs); however, the underlying mechanisms and kinetics of light-induced structural changes are not well understood. Herein, a double [2 + 2] photocyclization in photoactive [Cd 2 (stil) 2 (Py 2 TTF) 2 ] (stil 2− = 4,4′-stilbenedicarboxylic acid, Py 2 TTF = 2,6-bis(4′-pyridyl)-tetrathiafulvalene) offers a powerful platform to quantitatively probe solid-state photocyclization kinetics. Variable-temperature Raman spectroscopy revealed a nonlinear temperature dependence of these parameters, which could be analyzed using the Johnson−Mehl−Avrami−Kolmogorov (JMAK) kinetic model to yield a maximum rate observed between 0 °C and 20 °C of approximately 0.172 s −1 . These results offer the first example of the quantification of the photocyclization kinetics in a MOF. Density functional theory (DFT) calculations support a singlet reaction mechanism for the double [2 + 2] photocyclization, which is facilitated by the cofacial alignment of Py 2 TTF ligands. Establishing mechanistic and kinetic models that can be applied to multistimuli-responsive materials provides a powerful platform for their future design for applications in sensing, switching, and molecular separations.

In this work, we performed a techno-economic analysis for a one-pot, green mechanochemical synthesis of the archetypal metal−organic framework (MOF) UiO-66-NH 2 . The analysis demonstrated that labor costs play a substantial role in the cost of manufacturing. We identified the importance of scaling production from a batch method toward a more continuous synthesis mechanism. Through our work, we were able to mechanochemically produce UiO-66-NH 2 at a rate of 4.52 g per 90 min with a 43% yield for a levelized cost of approximately US $6,498 per kilogram, which is comparable in cost to other archetypal MOFs offered in retail markets.

The hybrid ultraporous material TIFSIX-Ni ([Ni-(pyrazine) 2 (TiF 6 )] n ) was incorporated into a composite ink for the first time for the three-dimensional (3D) printing of monoliths. The large-scale synthesis of TIFSIX-Ni was completed using two different Ni(II) salts, with CO 2 uptakes of 1.90 mmol g −1 achieved using mechanochemically assisted thermal synthesis. The monoliths were then tested for the capture and release of CO 2 gas using electric swing adsorption (ESA) under dry and humid conditions. A working capacity of 1.7% was achieved (comparing dynamic data with isotherm data) when a current of 2.1 A was applied for 10 min. The monolith could be cycled repeatedly for 6 h without impacting the performance of the material or loss of capacity. Part of this work explored the improvement of mechanochemically assisted synthetic methods of TIFISX-Ni in reducing the costs associated with large-scale production, allowing for improvements in the overall scale-up and processability of the material for industrial applications.

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