1. Laser-induced skutterudite SHS reaction process at room temperature

2. (a) Schematic diagram of room temperature and preheating SHS experiment; (b) Physical picture of the preheating module; (c-h) I. combustion wave front (t=0.95 s) and II. section photographs of powders compacts after SHS for sample Px(x=150, 200, 250, 300, 350, 400); (i) Trend graph of combustion temperature and combustion velocity changed with power density of ignition laser in CoSb₃ system

3. Four typical SHS performances in CoSb₃ system with different preheating temperatures

4. (a) Trend graph of combustion temperature changed with preheating temperature in CoSb₃ system and (b) variation trend of combustion rate around region 3

5. XRD patterns of compact powders after SHS in different preheating temperature ranges

S1. Schematic diagram of the SHS device

S2. XRD patterns of samples RT6.25, RT12.5 and RT25

S3. Time-dependent temperature graphs of sample Px at the thermocouple TC1 (black) and TC2 (red)

S4. Time-dependent temperature graphs of sample Tx(x=150, 160, 170, 200, 210, 220, 230, 240, 250, 330, 350, 380, 400) at the thermocouple TC1 (black) and TC2 (red)

S5. SE, BSE images ((a, c)×200, (b, d) ×5000) of (a, b) sample P300 and (c, d) sample T400

Table 1. Laser ignition process for SHS samples at room temperature

Table 2. Laser ignition process of SHS samples under preheating condition

Table 3. Area scanning and spot scanning results (Atomic percent) of samples P300 and T400