Meissner Effect in Colloidal Pb Nanoparticles

Abstract

Monodisperse colloidal lead nanoparticles with diameters ranging from 4.4 to 20 nm are prepared by a self-limiting growth method. The nanoparticles are monodispersed and protected from oxidation by an amorphous tin-lead oxide shell of 1.5-2 nm thickness. The magnetic susceptibility of the particles is measured as a function of size, temperature, and magnetic field. The Meissner effect is observed indicating the superconducting transition. For the 20 and 16 nm particles, the critical temperature is suppressed to 6.9 K from the bulk value of 7.2 K and is further reduced for smaller particles. Depending on the size of the particles, the critical field is enhanced by 60-140 times. The superconducting properties agree closely with the theoretical expectations.

Cluster Superconductivity in the Magnetoelectric Pb(Fe1/2Sb1/2)O3 Ceramics

“…5. One can see that our PFS ceramics data are in good coincidence with those in bulk testing sample and literature data [29,30] except the lowest temperatures where PFS exhibits higher critical fields due to size effects, i.e. the increase of the critical field in small particles [29,30].…”

Synthesis and Characterization of Pb@GaS Core–Shell Fullerene-Like Nanoparticles and Nanotubes

“…Part of the interest stems from recent studies showing the e®ect of the shape and size of Pb nanoparticles on their superconducting properties, [38][39][40][41][42][43] and intimating that Pb@GaS nanostructures may have novel superconducting properties -a topic for future investigations.…”

Direct Conversion of Bulk Metals to Size‐Tailored, Monodisperse Spherical Non‐Coinage‐Metal Nanocrystals

“…[1,[5][6][7][8] Monodisperse colloidalm etal NCs have also been regarded as ideal building units for advanced superstructures and devices. [1,[10][11][12] It is well-known that the colloidal chemistry is based on abottom-up strategy,where the neutral metal atoms need to be firstly released through either reduction or thermolysis of the precursors to initiate nucleation and subsequent growth of metal NCs.O wing to the intrinsic inertness,n oble metal NCs,s uch as Au and Pt, can be easily prepared by reduction of metal salts with alcohols. [1,[10][11][12] It is well-known that the colloidal chemistry is based on abottom-up strategy,where the neutral metal atoms need to be firstly released through either reduction or thermolysis of the precursors to initiate nucleation and subsequent growth of metal NCs.O wing to the intrinsic inertness,n oble metal NCs,s uch as Au and Pt, can be easily prepared by reduction of metal salts with alcohols.…”

“…[9] To date,s everal colloidal chemistry methods have been developed to synthesize monodisperse spherical metal NCs with controlled particle sizes. [10] In contrast, for the synthesis of non-noble metal NCs,r eactive organometallic precursors (that is,m etal carbonyls,m etal amides) or/and strong reducing agents (that is,superhydride, sodium borohydride) are prerequisite, [1,11,12] however, these are usually hazardous,c ostly,c omplex, and even lack availability.Herein, for the first time,wereport on arobust conversion strategy,f ree of precursors and reducing agents,w hich transforms bulk non-noble metals directly into ligand-protected, size-tailored, highly crystalline,m onodisperse spherical non-noble metal NCs,b yl ow-power nanosecond NIRlaser ablation/irradiation. [10] In contrast, for the synthesis of non-noble metal NCs,r eactive organometallic precursors (that is,m etal carbonyls,m etal amides) or/and strong reducing agents (that is,superhydride, sodium borohydride) are prerequisite, [1,11,12] however, these are usually hazardous,c ostly,c omplex, and even lack availability.…”