Yejun Qiu

Nickel-enhanced silver nanowire-based transparent heater with large size

An effective process for homogeneous electrodeposition of nickel was developed to improve the performance of silver nanowire-based transparent heaters (AgNW-THs). After electroplating Ni, the silver nanowires are uniformly coated by a layer Ni with 20–40 nm thickness, which has a small effect on the device transmittance, but significantly enhances its conductivity. Most excitingly, the nickel shell leads to a great increase of the temperature toleration of the AgNW-THs. A transparent tubular heater with large size of 3 cm in diameter and 20 cm in length is successfully fabricated, showing excellent heating properties in that the steady-state temperature can reach 284.3 °C and there is minimal variance in temperature after 10 heating cycles, and by using this tube, red Cu powder was oxidized into black CuO in a short time, which was visually observed. Additionally, two other shapes of transparent heaters with large size were constructed for dehydration of CuSO4·5H2O and burning of red phosphorus, respectively. This kind of transparent heater has wide applications requiring high transmittance, excellent temperature toleration and large size, especially for teaching experiment apparatus in a visual model.

Highly thermal-stable and transparent silver nanowire conductive films via magnetic assisted electrodeposition of Ni

In this study, a magnetic assisted electrodeposition process was developed to fabricate a hybrid silver nanowire conductive film with excellent performance. In the two-step fabrication process, the primary conductive film was dip-coated with a low concentration of AgNW ink, which gives decent conductivity and extraordinary transmittance. It is worth noting that the highly diluted ink solution is superior to a high concentration of silver nanowire ink, which is prone to aggregate and hard to redisperse. Next, a magnetic assisted electrodeposition process was applied to in situ grow a secondary metallic layer onto AgNWs, leading to a much better conductivity while maintaining the high transmittance, which well reconciles the contradictive requirements between transmittance and conductivity. Especially, thanks to the magnetic tuning effect, a unique Ni protective layer was formed to achieve prominent adhesion on the substrate without embedding the structure into any material. The conductivity of the Ni/AgNW-based TCFs has no obvious change even after heating at 400 °C for 30 min, which is by far the best thermal stability ever reported. In addition, the excellent electrical and optical performances (a typical sheet resistance of ca. 9.8 Ω sq−1 at a transmittance of ca. 95.3%) outperformed most of the existing AgNW-based TCFs. Two devices, including an HITSZ pattern of LED lights and a nanoheater, were fabricated to demonstrate the feasibility and the outstanding performance.