Direct ink writing (DIW) of energetic materials has been an area of interest for micro size charge. In this work, 3, 4‐dinitrofurazanofuroxan (DNTF) based composite was prepared with nitrocotton (NC) and Viton as binders by DIW. Scanning Electro Microscope (SEM) and X‐ray diffraction were employed to characterize the composite samples. The impact sensitivity and thermal decomposition of the composites were also tested and analyzed. In addition, the critical size of detonation and detonation velocity were measured. The results show that DNTF based composite has a high density with whose value is 1.785 g cm−3, reaching 93.16 % of theoretical maximum density (TMD). The particles in composites are spheroidal with size ranging from 1 to 2 μm. Compared with raw DNTF, the obtained composite has a lower impact sensitivity and higher thermal stability. Moreover, the composites exhibit excellent detonation properties, whose critical size of detonation is around 0.01 mm and the mean detonation velocity is 8580 m s−1 at the charging width of 1 mm. Furthermore, part performances of this composite are contrasted with previous reported CL‐20 based composite and show better characters.

Nano-2,2′,4,4′,6,6′-hexanitrostilbene (HNS) particles were successfully prepared by a mechanochemical (i.e., high energy milling) process without an organic solvent, which can be viewed as a green technology. The particle size, morphology, specific area, crystal phase, thermal decomposition properties, impact sensitivity, and short duration shock initiation sensitivity were characterized and tested. The diameter of milling HNS is about 89.2 nm with a narrow size distribution and without agglomeration of particles. The formation mechanism of nano-HNS can be viewed as the transformation from thin HNS sheets with a one-dimensional nanostructure to three-dimensional nanoparticles. The nano-HNS particles present a much higher Ea and lower impact sensitivity than purified HNS, revealing the outstanding safety properties. From the results of the short duration shock initiation sensitivity, 50% and 100% initiation voltages are decreased compared with those of HNS-IV, indicating the higher initiation sensitivity.

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Passive radiative cooling (PRC) involves the emission of thermal radiation into cold space and the reflection of solar radiation, which aims to cool and lower the temperature of objects. However, currently most radiative coolers have a white appearance which restricts their potential applications. We develop a coloured bilayer radiative cooling membrane using polyvinylidene fluoride/tetraethoxysilane (PVDF/TEOS) fibres, with incorporation of phase change materials (PCMs) and active dyes through a simple and large-area electrospinning process. In comparison to traditional emitters, PCM-incorporated colourful coolers provide energy storage capacity and colourful appearances. Our phase-transition-based colourful flexible film (PCFF) achieves a total solar reflectance of 0.81 and a mid-infrared (MIR) (8-13 μm) emissivity of 0.85 with superior mechanical strength and good hydrophobicity. We experimentally demonstrate that our PCFF can significantly reduce the temperature of objects exposed to direct sunlight, with a cooling effect of up to 9 ℃ compared to commercial fabrics of similar materials and colours. Our work provides a promising starting point for the design and manufacture of colourful and flexible thermal control films.