Nanowires useful as heterogeneous catalysts are provided. The nanowire catalysts are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons. Related methods for use and manufacture of the same are also disclosed.

A chemical mechanical polishing composition for polishing a substrate having a silicon oxygen material comprises, consists of, or consists essentially of a liquid carrier, cubiform ceria abrasive particles dispersed in the liquid carrier, and a cationic polymer having a charge density of greater than about 6 meq/g.

A chemical mechanical polishing composition for polishing a substrate having a silicon oxygen material comprises, consists of, or consists essentially of a liquid carrier, cubiform ceria abrasive particles dispersed in the liquid carrier, and a cationic polymer having a charge density of greater than about 6 meq/g.

A chemical mechanical polishing composition for polishing a substrate having a silicon oxygen material comprises, consists of, or consists essentially of a liquid carrier, cubiform ceria abrasive particles dispersed in the liquid carrier, and a cationic polymer having a charge density of less than about 6 meq/g.

A chemical mechanical polishing composition for polishing a substrate having a silicon oxygen material comprises, consists of, or consists essentially of a liquid carrier, cubiform ceria abrasive particles dispersed in the liquid carrier, a self-stopping agent, and a cationic polymer.

A gas sensor capable of detecting carbon dioxide and having high stability is provided. A carbon dioxide gas sensor comprising an insulating substrate 3 and a gas sensing layer 1 formed on one major surface of the insulating substrate 3 via electrodes 2, wherein the gas sensing layer 1 comprises: (a) one or more rare earth metal oxycarbonates represented by Ln.sub.2O.sub.2CO.sub.3, Ln being at least one rare earth metal element selected from Sc, Y, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Pr, Yb and Lu, the rare earth metal oxycarbonate containing a hexagonal rare earth metal oxycarbonate as a main component; or (b) monoclinic samarium dioxycarbonate,
a production method of the gas sensor, and a method of selectively producing crystal polymorphism of lanthanum dioxycarbonate represented by La.sub.2O.sub.2CO.sub.3 are provided.

Embodiments of the present disclosure generally relate to an apparatus and a method for cleaning a processing chamber. In one embodiment, a substrate support cover includes a bulk member coated with a fluoride coating. The substrate support cover is placed on a substrate support disposed in the processing chamber during a cleaning process. The fluoride coating does not react with the cleaning species. The substrate support cover protects the substrate support from reacting with the cleaning species, leading to reduced condensation formed on chamber components, which in turn leads to reduced contamination of the substrate in subsequent processes.

There is provided a lithium-iron-manganese-based composite oxide capable of providing a lithium-ion secondary battery which has a high capacity retention rate in charge/discharge cycles and in which the generation of a gas caused by charge/discharge cycles is suppressed. A lithium-iron-manganese-based composite oxide having a layered rock-salt structure, wherein at least a part of the surface of a lithium-iron-manganese-based composite oxide represented by the following formula is coated with an oxide of at least one metal selected from the group consisting of La, Pr, Nd, Sm and Eu:
Li.sub.xM.sup.1.sub.(y-p)Mn.sub.pM.sup.2.sub.(z-q)Fe.sub.qO.sub.(2-) wherein 1.05x1.32, 0.33y0.63, 0.06z0.50, 0<p0.63, 0.06q0.50, 00.80, yp, and zq; M.sup.1 is at least one element selected from Ti and Zr; and M.sup.2 is at least one element selected from the group consisting of Co, Ni and Mn.

A composite having a composition expressed by A.sub.nX.sub.yM.sub.m wherein, A represents a lanthanoid that is in a trivalent state at least partially or entirely, X represents an element that is a Group-2 element in the periodic table selected from the group consisting of Ca, Sr, and Ba, or a lanthanoid that is different from A, M represents an element that is a Group-1 element in the periodic table, a Group-2 element selected from the group consisting of Ca, Sr, and Ba, or a lanthanoid that is different from A and X, n satisfies 0<n<1, y satisfies 0<y<1, m satisfies 0m<1, and n+y+m=1.

A composite having a composition expressed by A.sub.nX.sub.yM.sub.m wherein, A represents a lanthanoid that is in a trivalent state at least partially or entirely, X represents an element that is a Group-2 element in the periodic table selected from the group consisting of Ca, Sr, and Ba, or a lanthanoid that is different from A, M represents an element that is a Group-1 element in the periodic table, a Group-2 element selected from the group consisting of Ca, Sr, and Ba, or a lanthanoid that is different from A and X, n satisfies 0<n<1, y satisfies 0<y<1, m satisfies 0m<1, and n+y+m=1.