Electrospray-assisted nanocalorimetry measurements

The deposition of uniform, small and properly located samples onto micro- and nano-calorimetry sensors remains a challenge and is a critical aspect of performing these measurements. Here, we describe an electrospray method to deposit a variety of materials over a well-defined area of a chip-based calorimeter for small scale thermal measurements. Electrospray provides a versatile technique for sample deposition. In this work, we demonstrate the deposition of a number of samples, including insoluble inorganic materials (aluminum nanoparticles and Ge2Sb2Te5 (GST)), soluble inorganic materials (ammonium nitrate), biomaterials (lipids) and soluble organic materials (polyethylene oxide films and polyacrylonitrile formed into fibers) onto chip nanocalorimeters. This technique greatly simplifies sample deposition and expands applications for chip-based calorimetry.