Gd Metal–Organic\nFramework Thin Film for On-Chip\nLocal Magnetic Refrigeration

Dense metal–organic\nframeworks with high spin\nparamagnetic\nnodes are competitive materials for cryogenic magnetic refrigeration,\nparticularly in applications for which local cooling is advantageous.\nWe focus on obtaining thin films of gadolinium formate, which has\na large volumetric magnetocaloric effect. Continuous and homogeneous\ndeposits of gadolinium formate are successfully formed on silicon\nby means of aerosol jet printing, with control over the film thickness\nfrom 0.35 μm up to 2.5 μm. The excellent cooling power\nof the deposits is evidenced via direct measurements of the cooling\nof a 200 μm silicon wafer down to sub-K temperatures by a single\ndemagnetization from 1 T and 2 K, thereby demonstrating the potential\nof this approach for on-chip local magnetic refrigeration.