On-Demand Picoliter-Level-Droplet Inkjet Printing for Micro Fabrication and Functional Applications.

With the advent of Internet of Things (IoTs) and wearable devices, manufacturing requirements have shifted toward miniaturization, flexibility, environmentalization, and customization. Inkjet printing, as a non-contact picoliter-level droplet printing technology, can achieve material deposition at the microscopic level, helping to achieve high resolution and high precision patterned design. Meanwhile, inkjet printing has the advantages of simple process, high printing efficiency, mask-free digital printing, and direct pattern deposition, and is gradually emerging as a promising technology to meet such new requirements. However, there is a long way to go in constructing functional materials and emerging devices due to the uncommercialized ink materials, complicated film-forming process, and geometrically/functionally mismatched interface, limiting film quality and device applications. Herein, recent developments in working mechanisms, functional ink systems, droplet ejection and flight process, droplet drying process, as well as emerging multifunctional and intelligence applications including optics, electronics, sensors, and energy storage and conversion devices is reviewed. Finally, it is also highlight some of the critical challenges and research opportunities. The review is anticipated to provide a systematic comprehension and valuable insights for inkjet printing, thereby facilitating the advancement of their emerging applications.

Efficient photocatalytic hydrogen production over ZnIn2S4 by producing sulfur vacancies and coupling with nickel-based polyoxometalate.

A composite catalytic system using sulfur-vacancy-containing ZnIn2S4-Sv as a light-harvesting material and nickel-based polyoxometalate Na6K4[Ni4(H2O)2(PW9O34)2] (Ni4POM) as a co-catalyst was developed. The Ni4POM/ZnIn2S4-Sv composite gave a good hydrogen production rate of 337.5 µmol h-1, a value 11.8 times higher than that of ZnIn2S4-Sv. The direction of electron transfer, from ZnIn2S4-Sv to Ni4POM, was verified using surface photovoltage spectra.

Metal-free aminofluorination of α-diazo 2H-benzopyran-4-one: convenient access to ß-fluoramides.

We have developed a convenient synthesis of a series of ß-fluoramides in 65% yield. The process involved a tandem fluorination/Ritter reaction to synthesize ß-fluoramides using α-diazo 2H-benzopyran-4-one compounds. Selectfluor was used as the electrophilic fluoride source in acetonitrile to build the ß-fluorinated quaternary carbon center and amide derivatives of 2H-benzopyran-4-one in one step. The products N-(2-(2-fluoro-2,3-dihydro-3-oxobenzofuran-2-yl)propan-2-yl)acetamides were a series of bifunctional compounds with a 2-fluoro-2,3-dihydro-3-oxobenzofuran motif and amide groups.