Preparation Of Metal Printing Electronic Ink And Its Application In Inkjet Printing

With the leap of electronic technology and the improvement of people's living standards,the electronics industry has ushered in a new round of vigorous development.The new electronic products need to be thin and flexible to meet people's requirements.Relying on the development of science and technology and the needs of the market,the printing electronics industry gradually developed into a sunrise industry.This industry can achieve preparing the new generation of flexible electronic products with the advantages of low cost,large-area manufacturing and quick speed,which possesses a quite considerable development prospects.Printed electronic ink is an important part of the composition of printed electronic materials and the development of print ink is the key component to the development of printed electronic materials.Metal conductive inks are considered as the focus component of printed conductive ink research because of the advantages of excellent conductivity,simple manufacturing process and good application prospects.Under the green economic development model,it's an inevitable trend to develop green chemistry and water-based system.In this paper,tannic acid stabilized silver nanoparticles(TA-Ag NPs)and tannic acid stabilized copper nanoparticles(TA-Cu NPs)were synthesized by simple chemical reduction method and were prepared into inks which were suitable for printing.The conductive inks were printed onto photopaper using inkjet printer.After sintering,conductive patterns were obtained and the applications in gas sensor were explored using the printed conductive patterns.The specific contents of the paper are as following:(1)The preparation of TA-Ag NPs conductive ink and the application in inkjet printingTA-Ag NPs were synthesized under room temperature by using silver ammonia as the precursor,tannic acid as stabilizer and reducing agent simultaneously.TA-Ag NPs were participated using ethanol after reaction and solid TA-Ag NPs were obtained which have good stability and could be stored without oxidation for several months.TA-Ag NPs were prepared into 1-10 wt% TA-Ag NPs solution and 25 vol% isopropanol was added to adjust the viscosity and surface tension to obtain TA-Ag NPs ink.The stability of TA-Ag NPs ink was excellent which could be stored for two weeks without precipitation.The TA-Ag NPs ink was transferred onto photo paper using EPSON R330 inkjet printer.When the concentration of TA-Ag NPs ink was 2.5 wt%,the print layer was 40,the sintering temperature was 200 °C and the sintering time was 100 min,the lowest resistance of the conductive pattern could be obtained(2 ?/?).At that condition,the thickness of the printed pattern was 3.23 ?m and the resistivity was 6.4×10-4 ?·cm.The printed pattern showed good stability and flexibility,and showed good adhesion toward paper substrate under tape test.Besides,when integrating into a circuit connected with LED,the LED could be lighted.(2)The preparation of interdigital electrode using TA-Ag NPs ink and application in gas sensorThe interdigital electrodes were prepared using 2.5 wt% TA-Ag NPs ink by R330 inkjet printer.The interdigital electrodes with different interdigital spacing were obtained and sintered under different temperatures.Sulfonated graphene/polyaniline composite(SRGO-PANI)served as the ammonia-sensitive material and was dropped on the surface of the interdigital electrode to prepare ammonia sensor.When the interdigital spacing of the interdigital electrode was 0.5 mm,the sintering temperature was 50 °C,the concentration of SRGO-PANI was 2 mg·mL-1,the ammonia sensor could achieve linear detection of ammonia gas with the concentration range from 25 ppm to 1000 ppm.The ammonia sensor showed good cycle stability and could maintain stable sensing performance under the continuous detection of three cycles.The interdigital electrodes prepared by inkjet printing show potential application prospects in the field of gas sensing.(3)The preparation of antioxide TA-Cu NPs conductive ink and the application in inkjet printingTA-Cu NPs were synthesized under room temperature by using copper hydroxide as the precursor,tannic acid as the stabilizer and antioxidant,and hydrazine hydrate as the reductant.The reaction lasted for 2 h and the product was freeze-dried directly to prepare solid TA-Cu NPs.This process did not introduce any impurities into the system and the post-treatment is simple which could omit the purification steps.TA-Cu NPs exhibited an extraordinarily excellent anti-oxidation power and no oxidation was observed even after being stored under ambient conditions for 90 days.TA-Cu NPs were prepared into 2.5 wt% TA-Cu NPs solution and 25 vol% isopropanol was added to adjust the viscosity and surface tension to obtain TA-Cu NPs ink.The stability of TA-Cu NPs ink was excellent which could be stored for 10 days without precipitation.The TA-Cu NPs ink was transferred onto photo paper using EPSON R330 inkjet printer.Conductive printed patterns with sheet resistance of 2.5 ?/? were achieved after printing 40 layers and sintering at 200 °C under N2 protection for 2 h.