Despite having many properties, Ti3C2Tx MXene lacks stability against oxidation. To exploit its applicability, the stability against oxidation needs to be improved. In this study, we have found an application of Ti3C2Tx MXene in polymer-dispersed liquid crystals (PDLC) based smart-windows which doesn't require additional treatment to MXene for preventing its oxidation. Before this application, the MXene surface passivation by a thin layer of UV-curable polymer NOA65 was also studied to estimate long-term stability against oxidation. In polymer passivated MXene, the sheet resistance increases by just 20% as compared to 800% in the case of non-passivated counterpart as studied up to 180 days. During this period, the transmittance of polymer passivated MXene film remains almost unchanged. These results encouraged the use of MXene-coated glass substrates as transparent conducting electrodes in PDLC-based smart-window applications. The NOA65 polymer used in smart-windows fabrication encapsulates the liquid crystals as well as it also preserves the MXene without any additional treatment to the MXene surface. The transparent conducting MXene electrodes and PDLC-based smart-windows maintain high transmittance of around 71% after 180 days as compared to 74% on day 1 at a voltage of 50 V.