Enhanced magnetic susceptibility in Ti₃C₂T_<i>x</i> MXene with Co and Ni incorporation

Magnetic nanomaterials are sought to provide new functionalities for applications ranging from information processing and storage to energy generation and biomedical imaging. MXenes are a rapidly growing family of two-dimensional transition metal carbides and nitrides with versatile chemical and structural diversity, resulting in a variety of interesting electronic and optical properties. However, strategies for producing MXenes with tailored magnetic responses remain underdeveloped and challenging. Herein, we incorporate elemental Ni and Co into Ti₃C₂T_<i>x</i> MXene by mixing with dilute metal chloride solutions. We achieve a uniform distribution of Ni and Co, confirmed by X-ray fluorescence (XRF) mapping with nanometer resolution, with Ni and Co concentrations of approximately 2 and 7 at% relative to the Ti concentration. The magnetic susceptibility of these Ni- and Co-incorporated Ti₃C₂T_<i>x</i> MXenes is one to two orders of magnitude larger than pristine Ti₃C₂T_<i>x</i>, illustrating the potential for dilute metal incorporation to enhance linear magnetic responses at room temperature.