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Molybdenum (Mo) sulfide catalysts supported on ZrO2, Al2O3, TiO2, CeO2, and SiO2 were prepared by the incipient wetness impregnation method and explored with respect to their catalytic activity and H2S dependence in the water gas shift (WGS) reaction. The highest WGS activity at 450 °C and S/Mo atomic ratio among all Mo sulfide catalysts investigated were observed for the Mo–S/ZrO2 catalyst. Moreover, the WGS activity of the Mo–S/ZrO2 catalyst was stable for 72 h of reaction, regardless of the presence of H2S in the feed. The extent of sulfidation of supported Mo–S catalysts increased with decreasing MoO3 reduction temperature in temperature-programmed reduction, which indicated a decreased strength of MoO3–support interactions. A comparison of fresh and used supported Mo catalysts suggested that the active Mo–S sites of the Mo–S/ZrO2 catalyst maintained their catalytic activity without the crystallization of Mo–S species during 72 h of WGS reaction. Therefore, ZrO2 was indicated by this study as a promising support for the Mo-based WGS catalysts.

Water gas shift (WGS) reaction is a key industrial process to produce hydrogen from CO and H2O. However, conventional Cu-based WGS catalysts are easily deactivated by sulfur compounds, which are ubiquitous in syngas. Cu–Pd nanoparticles of size 8–10 nm were synthesized as a function of the Cu/Pd ratios and investigated as promising sulfur-tolerant WGS catalysts. Significant improvement in the WGS activity was observed in the Cu–Pd catalysts after calcination at 800 °C in air. Pd addition enhanced the reducibility of CuO and Cu0 dispersion and limited the formation of CuAl2O4 spinel during calcination at 800 °C. The additional reducible and catalytically active CuO species was generated by the Cu migration from the CuO shell covering the Cu–Pd nanoparticles onto the γ-Al2O3 support during the 800 °C calcination. The optimal Cu–Pd catalyst characterized by the CuO/CuAl2O4 ratio of 2.37 showed the highest WGS activity, thermal stability, and sulfur tolerance among all Cu-based catalysts reported in this study.

The resistivity of halogen-free atomic layer deposition (ALD) TiN thin films was decreased to 220 μΩ cm by combining the use of a high-thermal stability nonhalogenated Ti precursor with a highly reactive nitrogen source, anhydrous hydrazine (N 2 H 4 ). TDMAT [tetrakis (dimethyl-amino)titanium], TDEAT [tetrakis(diethylamido)titanium], and TEMATi [tetrakis (ethylmethyl-amido)titanium] were compared to TiCl 4 as precursors for ALD TiN using N 2 H 4 as a coreactant. By minimizing the pulse length of the Ti-source precursor and optimizing the deposition temperature, the resistivity of TiN thin films deposited using these precursors was reduced to 400 μΩ cm for TDMAT (at 350 °C), 300 μΩ cm TDEAT (at 400 °C), and 220 μΩ cm for TEMATi (at 425 °C) compared to 80 μΩ cm for TiCl 4 (at 500 °C). The data are consistent with the lowest resistivity for halogen-free ALD corresponding to the organic precursor with the highest thermal stability, thereby allowing maximum ALD temperature. After optimization, TiN thin films were grown in horizontal vias, illustrating conformal and uniform TiN using both TiCl 4 and TEMATi in horizontal vias in patterned substrates.

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