Scheme 1. Deposition of aligned MIL-101(Cr)PEDOT on IDE for humidity sensing MIL-101(Cr) was prepared via a previously reported hydrothermal method by mixing Cr(NO3)3•9H2O and terephthalic acid in 20 mL MilliQ water and allowing the mixture to react at 218 °C for 18 hours. The corresponding MIL-101(Cr)PEDOT was prepared via the incorporation and in-situ polymerization of EDOT at 90 °C overnight using I2 as an oxidant (experimental details are in SI x). Powder X-ray diffraction (PXRD) confirmed that the integrity of the MIL-101(Cr) framework is retained after incorporation of PEDOT (Figure ). Fourier-transform infrared (IR) spectroscopy was used to confirm the presence of PEDOT in MIL-101(Cr)PEDOT based on the observation of additional peaks at 700 -1300 cm -1 compared to the spectrum for MIL-101(Cr) (Figure ). The successful incorporation of PEDOT and the consequential reduction in porosity was further corroborated by the decreased BET surface area of MIL-101(Cr)PEDOT from 3821 m 2 •g -1 to 1144 m 2 •g -1 (Figure ). The loading of PEDOT was estimated to be about 57 wt% PEDOT in MIL-101(Cr)PEDOT, based on thermogravimetric analysis (TGA) (Figure ). Scanning electron microscopy (SEM) images show the presence of deposited material on the surface of MIL-101(Cr) that is attributed to PEDOT, which was further confirmed by EDX analysis (Figure ). To measure the electrical conductivity of MIL-101(Cr)PEDOT, the corresponding powders (15 mg each) were pelletized, and the out-of-plane electrical conductivity was measured using copper electrodes and compared with MIL-101(Cr) and pure PEDOT (Figure ). The addition of PEDOT significantly enhances the electrical conductivity of MIL-101(Cr) by around 4000 times. Similarly, via drop casting the same amount of MIL-101(Cr) and MIL-101(Cr)PEDOT on IDEs (10 µL from 16.7 mg/mL dispersion), we again observed higher conductivity for MIL-101(Cr)PEDOT compared to MIL-101(Cr) (Figure , S6). Details on the conductivity calculations can be found in the SI under general methods and Scheme S1. We subsequently investigated the applicability of E-fields to assist in the spatioselective deposition of MIL-101(Cr) and MIL-101(Cr)PEDOT. To begin with, we selected organic solvents suitable for the formation of homogeneous MIL-101(Cr) dispersions. In this case, tetrahydrofuran (THF) with a dielectric constant ε = 7.6 was found to be suitable. In addition, its low boiling point (66 °C) allowed rapid drying of the MOF dispersions via mild heat application, rendering it appropriate for our drop-casting purposes.