A chemical synthesis experiment in a lab, with colorful powders and liquids in bottles and beakers, and a machine with steam rising from a reaction vessel.

he NiCo-BTC MOFs were synthesized by dissolving 860 mg of nickel nitrate/cobalt nitrate mixture, 300 mg H3BTC, and 2 g PVP in 60 mL DMF. After 10-min magnetic stirring, the homogeneous solution was sealed in a Teflon- coated autoclave and subjected to a 150 ◦ C temper-ature for 7 h. The obtained precipitate underwent ethanol washing and subsequent drying at 60 ◦ C (24 h). After this, the purple-pink NiCo-BTC powder underwent calcination in a tube furnace under air atmosphere at 400 ◦ C (heating rate: 5 ◦ C min 1 , duration: 3 h). Post-thermal treatment characterization revealed a chromatic transition from purple-pink to black upon formation of NiCo2O4, observed after natural cooling to ambient temperature. Finally, the NiCo2O4 ink was prepared by ultra-sonic dispersion in 0.5 wt% Nafion/ethanol solution (12 mg/mL con-centration), followed by precise drop-casting onto the SPE substrat See more