Study On Preparation And Properties Of Silver Nanowire/Cellulose Composite Flexible Thin Films

In recent years,the transparent conductive thin films with excellent transparency,conductivity and good flexibility have attracted growing attention with the rapid development of flexible electronic devices.Recnetly,the silver nanowires?AgNWs?based transparent conductive thin films have attracted extensive attention and research owing to the outstanding optical properties,electronic properties and flexibility.In this thesis,we have systematically investigated the optical properties,electronic properties,mechanical stability and heating characteristics of the composite thin films based on the silver nanowire/cellulose.The main conclusions and contents are as follows:1.Silver nanowires thin films were prepared by rod-coating on glass substrate.Effect of concentration,coating speed,coating cycles and heat treatment on the optical and electronic properties of films were investigated.The films with sheet resistance of lower than 10?/sq and transmittance of higher than 80%?including the glass substrate?can be obtained with the concentration of 3 mg/ml and the coating speed of 10 mm/s,as well as controlling the coating cycles and heat treatment.2.The composite films were prepared by coating silver nanowires on the surface of Chinese Xuan paper?CXP?.The thermal characteristics,the principles of heating and the application in the electro-thermochromic paper display devices were studied.The fabricated films exhibited high heating temperature?78.1°C?at low input voltage?3 V?and short response time less than 10 s,the principles of heating was theoretically analyzed,and the non-linear relationship between the steady-state temperature and input power was put forward,which is agreeing well with our experimental data.The composite films also presented good flexibility with the change of resistance as low as about 2.7%even after 2000 times bending tests.Finally,the electro-thermochromic paper display with good cyclic discoloration performance was fabricated using the AgNWs/CXP film heaters,with the thermochromic inks on the other side of the paper substrate.3.The transparent conductive thin films were prepared by embedding with silver nanowires in nano-cellulose fibers films.The composite films showed good optotical and electronic properties with resistance of 8.8?/sq and optical transmittance of 81.2%.,The composite films have presented good flexibility with the change of resistance lower than 3.5%even after 5000 times bending tests.The fabricated films also exhibited high heating temperature?98.8°C?at low input voltage?6 V?,with the highest heating rate of 22.75°C s^-1.Surface emissivity of samples decreases as AgNW film covered.Finally,the composite films can be completely dissolved after 24 hours in water,exhibiting favourable environmental friendliness.In this thesis,we studied the composite films based on the silver nanowires and cellulose-based substrate.The above results provide an experimental guidance and theoretical basis for preparation of transparent conductive thin films with high optical transmittance,conductivity and flexibility.It also instructive for the application of silver nanowire based conductive thin films in the green and flexible electronic diveces.