This research describes the p-type nanostalactites (p-type NS) with high photothermal conversion capability has been demonstrated by rapid INC process without extra heat treatment. In optical property, p-type NS has ultralow reflectance below 5 % and high light absorption due to rough structures in the broadband wavelength (350 nm-1100 nm). It looks like a black body. Silicon, an indirect band material, can release thermal energy during the recombination process of photo-generated electron-hole pairs. P-type NS converts photon energy into heat rapidly and then photothermal effect occurs. Then, the temperature change of p-type NS is faster in 10 second than bulk p-type silicon. These nanostructures can not only enhance thermal conversion efficiency but be regarded as a great heat absorber.