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DOI: 10.1002/aenm.201802917 Compared to other pseudocapacitive materials, CPs are attractive due to their facile synthesis, intrinsic conductivity, good flexibility, and high redox contributions.[7] Polyaniline (PANI), polypyrrole (PPy), and poly(3,4-ethylenedioxythiophene) (PEDOT) are among the commonly studied polymers for supercapacitors.[11] However, in spite of focus on improving the performance of CPs as anode materials,[7,11,12] efforts to match them with pseudocapacitive cathode materials are still underway. It is important to note that the target material needs to be stable under negative potentials in acidic electrolytes, because CPs show the best electrochemical performance in acidic electrolytes under positive potentials.[6] Currently available choices for negative electrodes are mostly carbons and metal oxides.[13] However, majority of carbon-based and metal oxide electrodes show hydrogen evolution under modest negative potentials in low-pH media.[14] Although carbons with a low content of surface functionalities may have an extended voltage window, they cannot match CP in capacitance due to lack of redox contribution to energy storage. Finding cathode materials with high pseudocapacitance in acidic electrolytes is still a challenge, which hinders practical use of CP in electrochemical capacitors. In search of negative electrodes for CP-utilizing asymmetric devices, MXenes may offer a viable option due to their metallic conductivity and high redox capacitance under negative potential in acidic electrolytes.[15] MXenes, a rapidly growing large group of 2D transition metal carbides, nitrides, and carbonitrides, have shown a great potential for a range of applications, particularly, for supercapacitors.[16,17] Specifically, delaminated Ti3C2Tx has shown outstanding capacitance values up to ≈1500 F cm−3 (380 F g−1) in aqueous electrolytes in a three-electrode configuration.[15] By using a set of electrochemical experiments coupled with in situ X-ray absorption spectroscopy (XAS), it has been shown that the changes in electrode potential correlate almost linearly to variations in the titanium oxidation state, confirming the predominantly pseudocapacitive charge storage mechanism in acidic electrolyte (1 m H2SO4). In another effort,[19] when charge storage mechanism was investigated using in situ Raman spectroscopy in three different sulfatecontaining aqueous electrolytes, it became clear that bonding between oxygen functional groups and hydronium ion from H2SO4 electrolyte occurs upon charging. During discharge, the reversible bonding/debonding alter the oxidation state of Ti, resulting in high redox capacitance in acidic electrolyte. In Conducting polymers (CPs) are attractive pseudocapacitive materials which show the highest capacitance under positive potentials in aqueous protic electrolytes. One way to expand their voltage window (thus energy density) in aqueous electrolytes is to manufacture asymmetric supercapacitors using distinctly different anodes. However, CPs lack matching pseudocapacitive anode materials that can perform well in protic electrolytes (e.g., sulfuric acid). 2D titanium carbide (Ti3C2Tx), MXene, as a universal pseudocapacitive anode material for a range of CPs, such as polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene) deposited on reduced graphene oxide (rGO) sheets, is reported here. All-pseudocapacitive organic–inorganic asymmetric devices with MXene cathodes and rGO–polymer anodes can operate in voltage windows up to 1.45 V in 3 m H2SO4. Most importantly, these devices show outstanding cycling performance, outperforming many reported asymmetric pseudocapacitors.