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Ti3C2TxMXene is a member of the recently discovered two-dimensional early transition metal carbide and nitride family of MXenes with potential applications in energy storage and heterogeneous catalysis at elevated temperatures. Here, we apply a suite of in situtechniques to probe Ti3C2TxMXene’s thermal evolutions, including in situX-ray diffraction (XRD), in situdiffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and integrated thermogravimetry–differential scanning calorimetry–mass spectrometry (TG-DSC-MS). In light of this set of in situinvestigations, we find heterogeneity in the layering of Ti3C2TxMXene revealed only at higher temperatures. Our findings present behavior up to 600 °C, particularly interlayer water and −OH surface end-capping groups. In one group of layers, their interlayer spacing shrinks as water deintercalates, but the other group of layers unexpectedly shows no change in the interlayer spacing. This is strong evidence that intercalants act as guest pillaring agents in the latter layering group, which stabilize these layers at higher temperatures while keeping the interlayer space accessible.

Power generation from electrochemical devices based on solid oxide fuel cells (SOFCs) is in great demand for both stationary and automotive applications to achieve carbon neutrality goals by 2050. In particular, SOFCs are known for their fuel-flexible operations; for example, SOFCs can operate on simple and complex renewable fuels (such as ethanol, natural gas, jet fuel, propane, etc.). Unlike H2-based fuel cells, liquid and hydrocarbon fuels in SOFCs adopt the existing fuel infrastructure and contribute to reducing greenhouse gas emissions significantly. This article presents the potential of using metal-based SOFCs (metal cells) as highly performing and durable power generators. The metal cells technology could be the most accessible solution for using SOFCs for versatile industrial needs.

A Metal-Supported-SOFC (MS-SOFC) has been modified by infiltrating a non-noble metal ceria-zirconia supported cobalt (Co/CZ) internal reforming catalyst to improve its reforming activity and inhibit the carbon deposition or coking under ethanol steam reforming conditions. Non-noble metal catalysts can still be deactivated during long-term cell operation in a severe coking-inducing environment. Therefore, an in-situ regeneration procedure was performed by pulsing air into the anode surface to burn the deposited carbon on the anode and catalyst layer during the cell operation. Upon the cell regeneration steps, the cell voltage was recovered to its initial condition at ~0.8 V, while the peak power density of the cell showed up to 116% recovery under H2and 111% recovery under ethanol. These data show that the air pulsing regeneration steps in the MS-SOFC can improve the lifetime by removing the coking deposit within the anode and further enhancing its electrochemical and catalytic activity.