The reaction of aqueous solutions of K2PdCl4 and K3Co(CN)6 results in gellike polymeric materials, characterized by bridging cyanides between the central metals of the adducts. These materials tend to be rigid in nature but contain in excess of 95% water by weight. We refer to these novel transition metal based hydrogels as cyanogels. In contrast to classic inorganic hydrogels these materials are not based on an oxide network. Dehydration of the cyanogels results in amorphous xerogels which maintain the initial polymeric structure of the cyanogel. Thermal processing of gels containing palladium and cobalt centers under an inert atmosphere at temperatures between 200 and 500 °C, produces a new metastable material. Sintering between 500 and 1000 °C produces ferromagnetic alloys, while processing under oxygen in the same temperature region gives the ceramic mixed oxide material PbCoO2, having the delafossite structure.

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Anhydrous HBr used in etch processing for the semiconductor industry requires strict impurity control. However, the gas cylinder material of construction plays a critical role in controlling and maintaining purity levels of the delivered HBr process gas and must be carefully selected. In this work Ni-lined AISI 4130 Cr-Mo steel cylinders are compared against the gas industry standard AISI 4130 Cr-Mo steel cylinders with regard to (a) surface roughness/area and oxide layer thickness after exposure to HBr and (b) the concentration of moisture in delivered HBr gas. Over the period of a year, the surface roughness increase of the polished Cr-Mo steel package doubles that of the Ni-lined package and the penetration of the oxide layer into the metal for the Cr-Mo steel is over 10 times that for the Ni surface. Finally the more inert surface of the Ni lining is shown to lower the moisture concentration in the HBr gas by ~4 times. These findings demonstrate that Ni-lined AISI 4130 Cr-Mo steel provides a superior package for Ultra High Purity HBr storage and delivery.

Anhydrous HBr used in reactive ion etch chemistries for the semiconductor industry requires strict control of impurities over time. Proper selection of cylinder materials strongly influences the purity of the HBr over the shelf life of the stored gas. In this work Ni-lined AISI 4130 Cr-Mo steel cylinders are compared to the gas industry standard AISI 4130 Cr-Mo steel cylinders and 316L SS cylinders regarding the generation of atmospheric impurities over the shelf life of the cylinders. In addition an accelerated aging process of water doping was executed to determine variances between materials. Over the period of 18 months, significant amounts of atmospheric impurities such as CH4, CO2, and H2 were generated in the water doped cylinders. However, the Ni lined cylinders inhibited the atmospheric impurity generation by as much as 20 times, compared to the Cr-Mo steel or 316L SS cylinders in the accelerated study. A similar affect was observed in the standard non-accelerated study. These results demonstrate that Ni lined Cr-Mo steel provides a superior package for anhydrous HBr, due to superior contamination control.