*3.1. Materials*

All air- or water-sensitive reactions were carried out in a nitrogen atmosphere using oven-dried glassware. All syntheses of oven-based **UiO66** and the derivative MOFs were carried out in explosionproof HERAtherm OMS-100 (Thermo Fisher Scientific, Waltham, MA, USA) ovens that had been pre-heated to a specific temperature. All sonication was carried out with a Fisher Scientific Ultrasonic Cleaner FS60 (Thermo Fisher Scientific, Waltham, MA, USA). Anhydrous solvents in Sure/Seal™ bottles were purchased from the Aldrich Chemical Company (Milwaukee, WI, USA) and used as received inside a nitrogen-filled KIYON Glovebox (Korea Kiyon Glovebox System, Seoul, South Korea). All other reagents were purchased from the Aldrich Chemical Company (Milwaukee, WI, USA) and used without further purification unless otherwise noted.

Powder XRD spectra were collected using a Rigaku Ultima IV multipurpose X-ray diffractometer equipped with Cu-Kα radiation and a fixed monochromator. The XRD was operated at 40 KV and 40 mA and a fixed time-scan mode with a 0.02-degree step width and 1 s/step count time used for data collected from 5 to 90 degrees.

For scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS), an FEI Quanta 400 environmental scanning electron microscope was used to collect high-resolution SEM images. The SEM was operated at an acceleration voltage of 30 KV and the working distance was 6.5 mm. An EDAX Apollo EDS system was used for EDS signal collection and analysis.

Transmission electron microscopy images were collected using a Thermo Fisher company TalosF200x model with a super X EDS system. Powder 1 or 2 was dispersed in isopropyl alcohol and sonicated for about 5 min. An amount of 20 μL of the dispersed solution was dropped over a 300 mesh copper/lacey carbon grid and dried at room temperature for TEM analysis.

For N2 gas sorption analysis, the MOF samples for analysis were heated under vacuum overnight at 150 ◦C to remove the solvents trapped within the pores prior to analysis. Following this, an ~50 mg sample was transferred to pre-weighed sample tubes and degassed at 150 ◦C for 3 h by a Micromeritics Flow prep 060 sample degassing system. After degassing, the MOF sample tubes were re-weighed to obtain the mass for the samples. Sorption data with the Brunauer−Emmett−Teller method (BET) and the Langmuir surface area (m<sup>2</sup>/g) measurements were collected at 77 K with N2 on a Micromeritics TriStar II 3020 surface area and porosity system adsorption analyzer. The BET surface area and pore volume of prepared MOFs are shown in Supplementary Materials Table S1.

For the continuous-flow reaction, the MOF catalyst was loaded in transparent 1/8" Radel ® tubing with an inner diameter of 1.55 mm. Glass wool was used to hold the catalyst inside the reactor. A syringe pump was used to pump the reaction solution through 1/16" peek tubing connected to the packed reactor capillary and placed in a water bath to control the temperature, as shown in Figure 1. Before starting all flow runs, the packed microreactor was run under the flow of pure solvent to remove any components from the catalyst bed and perform the pressure drop test. Then a syringe was loaded with the chemical solution of ethyl paraoxon at a concentration of 0.061 M in a bu ffer solution of 0.1 M N-methylmorpholine. Multiple samples were collected from each condition and analyzed using UV−Vis measurements calibrated beforehand based on the product concentration.

UV−Vis spectra were recorded using quartz cells with a path length of 10 mm at room temperature with a Perkin Elmer UV/Vis/NIR spectrophotometer model Lambda 950; analysis was carried out using the UVwinLab software. The spectral baseline was corrected with Cary Win UV software. Progress of the reaction was monitored by following the p-nitrophenoxide absorbance at 405 nm to avoid overlapping absorptions with other species. Yields were calculated based on the calibration run of para-nitrophenol solutions in known concentrations (Supplementary Materials Figure S16).
