Silver nanowire

Due to its high mechanical (144 MPa cm³/g) and electrical properties, CNT aerogel sheet ribbon stacks was used as a host of yarn electrode. Well-aligned MWNT forest (~400 um high and consisting of ~12 nm diameter nanotubes containing ~9 walls) was synthesized on a Si wafer using previously reported chemical vapor deposition (CVD) method^{38 (link)}. Commercially available Ag nanowire and Zn nanoparticle were used as energy storage functional guest materials. Silver nanowires with 115 nm of diameter and 20~50 μm of length dispersed in isopropyl alcohol suspension, zinc nanoparticles with ~50 nm, PVA (average M_w is 130,000), and zinc oxide were purchased from Sigma-Aldrich Corporation. Potassium hydroxide was from J. T. Baker.

Compound semiconductor layers (30 nm InGaAs, 8 nm InP, 310 nm InGaAsP, 8 nm InP) were grown on an InP substrate by metal-organic vapor phase epitaxy, and additional metal layers (10 nm Ti, 300 nm Ag, 30 nm Pt, 2000 nm Ag) were electron-beam evaporated. It was bonded to a silver-evaporated silicon wafer with BiSn solder foil for two minutes at 170 degrees Celsius using a flip-chip bonder (FC-150, Karl Suss). The low bonding temperature and short bonding time were used to minimize metal diffusion. The InP substrate was then removed by mechanical grinding and chemical etching. In the final step, silver nanowires (Sigma-Aldrich) dispersed in isopropanol were drop-casted by a micro-pipette, and the planar optical resonator structures were randomly formed in the two-dimensional metal nanowire network. The length and diameter of silver nanowires were 30 ± 10 μm and 120 ± 10 nm, respectively. To reduce the optical loss and enhance the nanowire-light interaction, single crystalline nanowires with a thin dielectric cladding layer (~1.5 nm) were used (Fig. 1e). The optical effects of the cladding layer are examined as in Fig. S12a, and the reflectivity degradation from the cladding layer with a thickness of <2 nm was found to be minimal. We also investigated the effects of nanowire diameter on reflectance in Fig. S12b.