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A hyperbranched polyethylene (HBPE) is employed herein for noncovalent nonspecific functionalization and solubilization of multi‐walled carbon nanotubes (MWCNTs) in organic solvents. Though constructed solely from ethylene without any specific functionality, this unique hyperbranched polymer has been found to effectively solubilize MWCNTs at surprisingly high concentrations (up to 1 235 mg · L−1) in organic solvents such as chloroform and THF. These solubilities are comparable to and even better than the reported best values obtained through noncovalent specific functionalization with conjugated polymers capable of forming specific π‐π interaction with nanotubes in organic solvents. TEM and XRD results confirm that the nanotubes are completely exfoliated and debundled/de‐entangled upon functionalization with HBPE.

Interconnect formation is critical for the assembly and integration of nanocomponents to enable nanoelectronics- and nanosystems-related applications. Recent progress on joining and interconnect formation of key nanomaterials, especially nanowires and carbon nanotubes, into functional circuits and/or prototype devices is reviewed. The nanosoldering technique through nanoscale lead-free solders is discussed in more detail in this Review. Various strategies of fabricating lead-free nanosolders and the utilization of the nanosoldering technique to form functional solder joints are reviewed, and related challenges facing the nanosoldering technique are discussed. A perspective is given for using lead-free nanosolders and the nanosoldering technique for the construction of complex and/or hybrid nanoelectronics and nanosystems.

PbSe/CdSe core/shell nanocrystals with quantum yield of 70% were obtained by the “successive ion layer adsorption and reaction” technology in solution. The thickness of the CdSe shell was exactly controlled. A series of spectral red shifts with the CdSe shell growth were observed, which was attributed to the combined effect of the surface polarization and the expansion of carriers’ wavefunctions. The stability of PbSe nanocrystals was tremendously improved with CdSe shells.

Nanoscale lead-free solders (“nanosolders”) have been synthesized directly onto multisegmented metal nanowires using an electrodeposition method in nanoporous templates. The nanosolders fabricated include tin (Sn), tin/silver (Sn/Ag), and indium (In), and the diameter of the nanosolder nanowires ranges from 30 nm to 200 nm and the length from 1 to 10 μm. The microstructures of the lead-free nanosolders on nanowires have been characterized using optical microscopy and electron microscopy including a field-emission scanning electron microscope (FESEM) and a transmission electron microscope (TEM), along with energy-dispersive X-ray spectroscopy (EDS). Thermal properties of lead-free nanosolders on nanowires were characterized using a temperature-programmable furnace tube under a controlled atmosphere. It was found that nitrogen plays an important role in the nanosolder reflow process. The effect of base layer, barrier layer, and wetting layer on nanosolder reflow was studied, and an optimal nanowire nanosolder system with effective barrier and wetting layers was obtained. A liquid phase-based solder reflow process was developed, in which the nanosolder nanowires were assembled in a liquid medium and solder joints were formed between nanowires.