“…[3][4][5][6][7] The ability to analyze solids directly, and the ease of preparation, low detection limit (down to ng•g −1 ) and minimal matrix effects have made GD-MS useful for accurate determination of trace and ultra-trace elements in solid materials. [8][9][10][11][12] Although GD-MS has been widely used in advanced materials, geology, environmental science, and other fields, it usually requires conducting material to support the discharge of the insulators because of poor sample conductivity. [13][14][15][16][17][18] The introduction of a radio-frequency (rf) source into GD-MS allows direct analysis of conductive and non-conductive samples, either bulk solids or layered materials.…”