▎ 摘　　要

Spin caloritronic devices are multifunctional devices that combine spintronics with caloritronics and are set to play significant roles in low-power-consumption systems. In this work, the magnetic properties of nitrophenyl diazonium (NPD)-functionalized graphene (NPDG) sheets with NPD coverage ratios of 1:8, 1:18 and 1:32 are presented. The stable ground states of these sheets have ferromagnetic (FM) configurations and their Curie temperature (T-C) values are 540 K, 444 K and 157 K, respectively. The thermal spin transport properties of the NPDG sheets (with two transport directions: zigzag edge and armchair edge) with the NPD coverage ratio of 1: 8 are presented. For the zigzag edge, when a temperature gradient was produced between two electrodes, the spin-up and spin-down currents were driven in opposite directions, which indicated the appearance of the spin-dependent Seebeck effect (SDSE). In addition, a spin caloritronic device could be obtained in the form of a spin-dependent Seebeck diode (SDSD). For the armchair edge, when the temperature of the left contact increased beyond a critical value, the thermal spin-up current then increased remarkably from zero, while the thermal spin-down current remained approximately equal to zero over the entire temperature region, thus indicating the formation of a thermal spin filter. Finally, in terms of its behavior with respect to the charge current (I-ch), the spin-up thermopower (S up arrow) was found to be nearly equal to the spin-down thermopower (S down arrow); consequently, the charge thermopower must be nearly zero, thus further demonstrating that the SDSE has been generated. Our results indicate that NPDG sheets can be designed to produce high-efficiency spin caloritronic devices for room temperature operation.