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Wafer scale transition metal dichalcogenide films grown by MOCVD using two different chalcogen precursors are assessed for layer homogeneity and quality. These characteristics are then compared to electrical properties on the growth substrate. 

Abstract Lightweight energy storage devices are essential for developing compact wearable and distributed electronics, and additive manufacturing offers a scalable, low‐cost approach to fabricating such devices with complex geometries. However, additive manufacturing of high‐performance, on‐demand energy storage devices remains challenging due to the need for stable, multifunctional nanomaterial inks. Herein, the development of 2‐dimensional (2D) titanium carbide (Ti₃C₂T_xMXene) ink that is compatible with aerosol jet printing for energy storage applications is demonstrated. The developed MXene ink demonstrates long‐term chemical and physical stability, ensuring consistent printability and achieving high‐resolution prints (≈45 µm width lines) with minimal overspray. The high‐resolution aerosol‐jet printed MXene supercapacitor achieves an areal capacitance of 122 mF cm⁻²and a volumetric capacitance of 611 F cm⁻³, placing them among the highest‐performing printed supercapacitors reported to date. These findings highlight the potential of aerosol jet printing with MXene inks for on‐demand, scalable, and cost‐effective fabrication of printed electronic and electrochemical devices. 

Historically, high carbon steels have been used in mechanical applications because their high surface hardness contributes to excellent wear performance. However, in aggressive environments, current bearing steels exhibit insufficient corrosion resistance. Martensitic stainless steels are attractive for bearing applications due to their high corrosion resistance and ability to be surface hardened via carburizing heat treatments. Here three different carburizing heat treatments were applied to UNS S42670: a high-temperature temper (HTT), a low-temperature temper (LTT), and carbo-nitriding (CN). Magnetic force microscopy showed differences in magnetic domains between the matrix and carbides, while scanning Kelvin probe force microscopy (SKPFM) revealed a 90–200 mV Volta potential difference between the two phases. Corrosion progression was monitored on the nanoscale via SKPFM and in situ atomic force microscopy (AFM), revealing different corrosion modes among heat treatments that predicted bulk corrosion behavior in electrochemical testing. HTT outperforms LTT and CN in wear testing and thus is recommended for non-corrosive aerospace applications, whereas CN is recommended for corrosion-prone applications as it exhibits exceptional corrosion resistance. The results reported here support the use of scanning probe microscopy for predicting bulk corrosion behavior by measuring nanoscale surface differences in properties between carbides and the surrounding matrix.