A droplet micro‐reactor was developed to realize the internal sol–gel reaction of ZrO2 inside the droplet. The reactants are only allowed to combine when the droplet forms, meanwhile, they are able to mix well and react to form gel particles with a proper designed structure of the micro‐reactor. In this condition, the mixing efficiency was determined by the structure of the micro‐reactor and the flow rate ratio of the two components. After sintering, ZrO2 ceramic microspheres are acquired with high sphericity and narrow size distribution. This droplet micro‐reactor overcomes the gelation of the premixed sol and reactant in the channel, and it has been demonstrated to be more stable with a longer running time.

The mixing of a polyacid cross-linker with a pyridinium-functionalized anthracene amphiphile afforded a supramolecular hydrogel through a self-assembly process that was primarily driven by π-stacking and electrostatic interactions.

The mechanism of the carbon-nitrogen coupling reaction of 2-iodo-selenophene with benzamide catalyzed by CuI has been investigated with density functional theory at the GGA/PW91/DND and GGA/PBE/DNP levels. The geometric configurations of the reactants, intermediates, transition states, and products were optimized and verified by means of vibration frequency calculations. A four-step mechanism was proposed for the reaction. The first step was the rate-control step. Two possible pathways in the fourth step were investigated, and the main pathway was identified by comparing their activation and dissociation energies. For comparison, the same calculations were performed to the reaction without the CuI activator. The activation barrier with CuI is 76 kJ mol(-1) smaller than that without CuI. It turns out that CuI can promote the reaction by lowering the activation energy. Our calculations reveal the crucial role of CuI in the reaction and agree well with experimental findings.

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