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Batteries are one of today's best ways to store energy chemically, which will be necessary for a green energy shift. Sodium-ion batteries (NIBs) offer an affordable and abundant alternative to Lithium-ion batteries (LIBs). One promising cathode material for NIBs is Prussian White (PW) which is an earth-abundant, low-cost material choice. Water has been seen to modulate the electrochemical response of PW but is unwanted in a battery as it has low electrochemical stability and thus participates in side reactions. The aim of this thesis is to determine the impact of other neutral guest species on the electrochemical properties and structure of PW. To achieve this, methods for synthesis and solvent exchange were developed. After iterations of synthesis, high-quality rhombohedral PW was obtained. The as-synthesised powder was solvent exchanged with ethanol and acetonitrile. Pristine and solvent exchanged samples were analysed with X-ray diffraction (XRD) and thermogravimetric analysis (TGA) to determine structure and composition. No substantial change after solvent exchange could be seen in the structure, XRD, while TGA indicated that a solvent exchange occurs for ethanol. Commercial electrodes were also investigated through complete dehydration followed by rehydration in ethanol and acetonitrile. The acetonitrile exchanged samples showed a similar electrochemical response during galvanostatic cycling as hydrated PW while ethanol did not alter the electrochemical properties. The results show that a solvent exchange does take place for both ethanol and acetonitrile and that acetonitrile also changes the electrochemical properties of PW.