One-pot reaction among [(Cp)2Mo2(CO)6], elemental sulfur, and dimethyl acetylenedicarboxylate (DMAD) affords several types of dinuclear molybdenadithiolene complexes. The thermal reaction gives [(Cp)(CO)2Mo{μ-S2C2(CO2Me)2}2Mo(Cp)] (2), while the photoreaction gives mainly isomeric [(Cp)Mo(CO){μ-S2C2(CO2Me)2}2Mo(CO)(Cp)] (3). The former dicarbonylmolybdenum complex easily undergoes decarbonylation, while the latter is thermally stable.

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Plasma‐damage during the dry‐etch process often induces degradation of the electric performance in GaN high electron mobility transistor (HEMT) devices. In this paper, the effects of wet‐etch processing on plasma‐damaged AlGaN films using various chemical solutions and propose the best chemical formulation are reported. Three chemical solutions are selected by a combinatorial method. A MIS‐capacitor TEG is fabricated on an AlGaN/GaN structure, and each surface is evaluated by XPS, SIMS, TEM, and AFM. From the results of C–V measurements of wet‐etched samples, the study reveals that the wet chemicals successfully remove charge traps at ≈−2.3 eV induced by the dry‐etch process. Moreover, these C–V results show excellent agreement with simulated trap models. The XPS results show that O/Ga ratios increase from 0.32 to 1.00 after the dry‐etch process, whereas after the wet‐etch process, the ratios return to less than 0.31. Moreover, the TEM observations reveal that an amorphous layer is only detected in the dry‐etched sample. Therefore, this amorphous layer should be an oxidized AlGaN layer. Thus, the selected chemical formulation can successfully remove the damaged‐layer induced by the dry‐etch process. The increase of surface roughness by the wet‐etch process is suppressed less than 0.1 nm.

Anion exchange membrane fuel cells have several advantages compared with proton exchange membrane fuel cells such as faster electrochemical reaction process, minimization of the corrosion issues, and enabling to use non platinum group metal as catalyst. On the other hand, electrospray deposition is a suitable way to prepare a nano/micro-structured layer. It is easy to construct, and each particle dropped from the tip of a needle is electrically charged and self-disperses in the space. Droplets deposit on the substrate homogeneously. In this paper, electrospray deposition was used to fabricate the catalyst layers for anion exchange membrane fuel cells. The conditions for electrospray deposition was determined with try and error. Furthermore, the relation of the ratio between carbon and ionomer was investigated to optimize the catalyst ink of fuel cells.