Photochromic materials have been extensively studied because they are quite attractive and promising for many applications.

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Outdoor heat stress can cause health hazards for workers and reduce labor productivity, thus leading to an annual burden of US $6.2 billion for the Australian workforce. Because the outdoor temperature fluctuates within a day, self‐regulating textiles are urgently needed to keep the temperature of the human body stable. Smart textiles are able to sense their surrounding environment and can respond by adapting their behaviors accordingly. However, there are a number of challenges in utilizing functional materials to achieve smart thermal radiation management for outdoor comfort and energy saving without using an external power supply. Here, a smart textile with thermal radiation management is designed by combining vanadium dioxide (VO2) and silver (Ag) strips on polyester (PET). This well‐designed VO2/Ag–PET exhibits high thermal management efficiency with a decrease of 13.9 °C at in‐box temperature under intense radiation while remaining transparent to thermal radiation at low temperature. Moreover, the VO2/Ag–PET shows good thermoresponsive and anisotropic electrical conductivity. In addition, it maintains 95% of its performance after bending. The proposed VO2/Ag–PET textile has the potential to be used for thermal management, for wearable and flexible communication devices, and for energy saving applications.

Aggregation of two-dimensional (2D) nanosheet fillers in a polymer matrix is a prevalent problem when the filler loading is high, leading to degradation of physical and mechanical properties of the composite. To avoid aggregation, a low-weight fraction of the 2D material (<5 wt %) is usually used to fabricate the composite, limiting performance improvement. Here, we develop a mechanical interlocking strategy where well-dispersed high filling content (up to 20 wt %) of boron nitride nanosheets (BNNSs) can be incorporated into a polytetrafluoroethylene (PTFE) matrix, resulting in a malleable, easy-to-process and reusable BNNS/PTFE composite dough. Importantly, the well-dispersed BNNS fillers can be rearranged into a highly oriented direction due to the malleable nature of the dough. The resultant composite film has a high thermal conductivity (4408% increase), low dielectric constant/loss, and excellent mechanical properties (334%, 69%, 266%, and 302% increases for tensile modulus, strength, toughness, and elongation, respectively), making it suitable for thermal management applications in the high-frequency areas. The technique is useful for the large-scale production of other 2D material/polymer composites with a high filler content for different applications.

In article number 1900599, Xuchuan Jiang and co‐workers present a smart textile with thermal radiation management, which is designed by combining vanadium dioxide (VO2) and silver (Ag) strips on a flexible polyester (PET). The VO2/Ag‐PET material exhibits high thermal management efficiency with decrease of 13.9 °C at in‐box temperature under intense radiation, while remains transparent to thermal radiation at a low temperature. Moreover, this smart textile shows good thermoresponsive and anisotropic electrical conductivity with a good bending stability.