In this work we present 3 showcases that luminescence thermometry is a promising and versatile technique for temperature monitoring in various microfluidic devices.

In this review article, we discuss the latest advances and future perspectives of microfluidics for micro/ nanoscale catalyst particle synthesis and analysis. In the first section, we present an overview of the different methods to synthesize catalysts making use of microfluidics and in the second section, we critically review catalyst particle characterization using microfluidics. The strengths and challenges of these approaches are highlighted with various showcases selected from the recent literature. In the third section, we give our opinion on the future perspectives of the combination of catalytic nanostructures and microfluidics. We anticipate that in the synthesis and analysis of individual catalyst particles, generation of higher throughput and better understanding of transport inside individual porous catalyst particles are some of the most important benefits of microfluidics for catalyst research. SynthesisThis section focuses on the most recent approaches within the last 8 years. For a more extensive overview of the synthesis of nanostructures focused on the processes taking place inside the microfluidic systems, 5 the final application 4 or the microfluidic technology used 6,7 we refer the reader to other review articles. Metal nanoparticlesMetal nanoparticles exhibit very interesting catalytic, optical, chemical, electromagnetic and magnetic properties, all of them depending to a large degree on their size and composition. Regarding catalysis, a decrease of the NP size leads to a surface-area increase per mass, providing more active sites. Also, the surface structure is of vital importance for the NP selectivity: the presence of steps, edges or terraces in the atomic surface can influence the reaction pathways to Lab Chip, 2019, 19, 3575-3601 | 3575 This journal is

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The role that the α-Fe2O3/NiFeOOH interface plays in dictating the oxygen evolution reaction (OER) mechanism on hematite has been a source of intense debate for decades, but the chemical characteristics of this interface and its function are still ambiguous and subject to speculation. In this study, we employed operando X-ray absorption spectroscopy to investigate the interfacial dynamics at the α-Fe2O3/NiFeOOH interface. We uncovered the spontaneous formation of a FeOOH interfacial layer under (photo)­electrochemical conditions. This FeOOH interfacial layer plays a role in the surface passivation of hematite and in accumulating the (photo)­generated holes upon external potential application. This hole-accumulation process leads to the extraction of more (photo)­generated holes from hematite before releasing them to NiFeOOH to carry out the water-splitting reaction, and it also explains the reason for the delay in the nickel oxidation process. Based on these observations, we propose a model where NiFeOOH acts mainly as an OER catalyst and a facilitator of holes extraction from hematite, while the interfacial FeOOH layer acts as a surface passivation and hole-accumulation overlayer.

A major challenge for the development of a wearable artificial kidney (WAK) is the removal of urea from the spent dialysate, as urea is the waste solute with the highest daily molar production and is difficult to adsorb. Here we present results on glucose degradation products (GDPs) formed during electrooxidation (EO), a technique that applies a current to the dialysate to convert urea into nitrogen, carbon dioxide, and hydrogen gas. Uremic plasma and peritoneal effluent were dialyzed for 8 hours with a WAK with and without EO‐based dialysate regeneration. Samples were taken regularly during treatment. GDPs (glyoxal, methylglyoxal, and 3‐deoxyglucosone) were measured in EO‐ and non‐EO‐treated fluids. Glyoxal and methylglyoxal concentrations increased 26‐ and 11‐fold, respectively, in uremic plasma (at [glucose] 7 mmol/L) and 209‐ and 353‐fold, respectively, in peritoneal effluent (at [glucose] 100 mmol/L) during treatment with EO, whereas no change was observed in GDP concentrations during dialysate regeneration without EO. EO for dialysate regeneration in a WAK is currently not safe due to the generation of GDPs which are not biocompatible.

Since inter- and intra-particle heterogeneities in catalyst particles are more the rule than exception, it is advantageous to perform high-throughput screening for the activity of single catalyst particles. A multiphase...

In this paper, we report on a capillary microfluidic device with constant flow rate and temperature-triggered stop valve function. It contains a PDMS channel that was grafted by a thermo-responsive...

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