Translation from batch to continuous processing of metal nanoparticle synthesis and application metallic nanostructures printed on flexible substrates

Abstract

One of the key challenges in nanoparticle synthesis is the quality control on scaling up the operation from bench to plant scale, which is constrained by conventionally adopted batch operation. Translation from batch operation to continuous green synthesis (metal, bi-metallic core-shell, and alloy nanoparticles (NPs)) with low polydispersity index (PDI) could unlock potential applications of metallic nanostructures with a projected market of $40.6 Billion and more by 20271. However, the continuous large-scale production suffers from high polydispersity due to lack of process optimization. We attempt to address such scale-up challenges while using the green synthesis of metallic nanoparticles in this work. The objective of this thesis is to optimize continuous processing of metal nanoparticle synthesis and demonstrate application of metallic nanostructure printed of flexible substrate using inkjet printing technology. The first part of the thesis is motivated by the desire to translate the batch protocol for NPs synthesis (developed in our group earlier)2,3 to a continuous process, and hence increase the affordability of NPs for end users. In this work, nanoparticle colloids are synthesized using different designs of CFRs and steady-state synthesis of nanoparticles is achieved with insignificant variation in particle size. Our results further showed that a balance between engineering and chemical parameters are required to obtain desired particle size distribution (PSD) and morphology during green synthesis of NPs. We improved our reactor design from channel to pool-based to address poor reagent mixing and our results show that the pool reactors could produce uniform particles of sizeii 7.2±1.0 nm with the production rate of 7.1 mg/h. We later moved to a CSTR-based reactor to address variations in the particles morphology while changing the flow rate of precursor salt...