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We combined microcontact printing (μCP), the chemical modification of surfaces, and the binding and reduction of metal ions to produce arrays of metal clusters and metal patterns. Pd²⁺ was bound in and at polyamine–amide (PAMAM) dendrimer molecules with potential ligands (amides and amines or carboxylate). Pd clusters formed after reduction. They provided chemically well-defined nuclei for the electroless deposition of metals. After producing a passivation pattern with μCP, deposition occurred only on those pixels or lines that were covered with Pd clusters. The method is quite general, as exemplified by two different passivation examples, alkanethiolate on gold and alkylsilane on oxidized silicon wafers.

We combined microcontact printing (μCP), the chemical modification of surfaces, and the binding and reduction of metal ions to produce arrays of metal clusters and metal patterns. Pd2+was bound in and at polyamine–amide (PAMAM) dendrimer molecules with potential ligands (amides and amines or carboxylate). Pd clusters formed after reduction. They provided chemically well‐defined nuclei for the electroless deposition of metals. After producing a passivation pattern with μCP, deposition occurred only on those pixels or lines that were covered with Pd clusters. The method is quite general, as exemplified by two different passivation examples, alkanethiolate on gold and alkylsilane on oxidized silicon wafers.

Bi(2223)/Ag tapes with CrO3 doping have been fabricated by Powder-in-Tube (PIT) method. It is found that a small amount of CrO3 doping improves the flux pinning, with the effective pinning center due to Cr substitution for Cu, while excessive Cr-ion doping degrades the superconductivity of Bi(2223). XRD analysis shows that a small amount of CrO3 addition has no effect on the phase composition of Bi(2223)/Ag tape. SEM micrographs of Bi(2223) tapes do not show a distinct difference between the pure sample and CrO3 doped samples (x ≤ 0.4%).

MgO nanorods with the average diameter of 30 nm and the length of 2 to 3 μm have been incorporated into (Bi, Pb)-2223 superconductors. The differential thermal analysis (DTA) measurements show that the addition of MgO nanorods results in the lowering of the melting point of the samples, which indicates that the optimum formation temperature of (Bi, Pb)-2223 phase is reduced. X-ray diffraction (XRD) analysis manifests that a small addition of MgO nanorods does not obstruct the formation of (Bi, Pb)-2223 phase. Furthermore, the transmission electron microscopy (TEM) observation shows that the MgO nanorods do not agglomerate or grow during the sintering process, which is crucial to the further application of MgO nanorod doping in (Bi, Pb)-2223/Ag tapes. The ac susceptibility measurements indicate that a small addition of MgO nanorods enhances the intergrain critical current density Jc significantly. The enhancement of Jc originates from the improvement of intergrain coupling due to the MgO nanorod doping.

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