Amorphous NiFe Nanotube Arrays Bifunctional Electrocatalysts for Efficient Electrochemical Overall Water Splitting

It is still a challenge for design and fabrication of cost-effective and efficient bifunctional electrocatalysts for both cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) for overall water splitting. Herein, we design and synthesize amorphous NiFe nanotube arrays on nickel foam (NiFe NTAs-NF) with high electrocatalytic activity and excellent durability for both OER and HER in overall water splitting. The as-synthesized NiFe NTAs-NF only requires relatively low overpotentials of 216 mV for the OER and 181 mV for the HER to reach current densities of 50 and 10 mA cm^–2, respectively. Moreover, when used as bifunctional catalysts for water splitting, the designed electrode only needs a low cell voltage of 1.62 V to obtain 10 mA cm^–2 for the overall water splitting, with an extremely excellent durability. The excellent performance of the NiFe NTAs-NF might be attributed to the synergistic effect and amorphous phase of NiFe alloy as well as the well-defined nanotube array architecture with large surface area, abundant active sites, and sufficient gas and electrolyte diffusion channels

Sn-Nanorod-Supported Ag Nanoparticles as Efficient Catalysts for Electroless Deposition of Cu Conductive Tracks

The applications of tin are extremely wide-ranging, in fields as diverse as Li-ion batteries, catalysis, and electronic packaging. It is always significant but still remains a great challenge to develop facile and efficient routes to synthesize Sn nanostructures. Herein, we report a facile chemical method to synthesize a Sn nanorod crystal at room temperature, and Ag ions are subsequently introduced to form the Sn-nanorod-supported Ag nanoparticles hybrid structure (Sn/Ag nanorods). The Sn/Ag nanorods exhibit comparable activity to the commercial Pd black in catalyzing the electroless copper deposition (ECD) reaction that is indispensable to fabricate printed circuit boards (PCBs). Furthermore, a screen printable adhesive is prepared by mixing the as-synthesized Sn/Ag nanorod powders and epoxy resin to fabricate activator patterns on epoxy laminate (EPL) and flexible substrates including polyethylene terephthalate (PET) and polytetrafluoroethylene (PTFE) fiber film. The printed areas are finally metalized by the ECD process to obtain the copper coatings with designed patterns that are confirmed to exhibit excellent electrical conductivity and flexibility

Electroless Deposition Metals on Poly(dimethylsiloxane) with Strong Adhesion As Flexible and Stretchable Conductive Materials

A new surface modification method is developed for electroless deposition of robust metal (copper, nickel, silver) layers on poly­(dimethylsiloxane) (PDMS) substrate with strong adhesion. Under the synergies of the polydopamine (PDA), the plasma process enhances Ag⁺ reduction, and a thin Ag film is capable of tightly attaching to the PDMS surface, which catalyzes electroless deposition (ELD) to form robust metal layers on the PDMS surface with strong adhesion. Subsequently, a flexible and stretchable Cu-PDMS conductor is obtained through this method, showing excellent metallic conductivity of 1.2 × 10⁷ S m^–1, even at the longest stretch strain (700%). This process provides a successful strategy for obtaining good robust metal layers on PDMS and other polymer substrate surfaces with strong adhesion and conductivity