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The authors reveal a thermal actuating bilayer that undergoes reversible deformation in response to low‐energy thermal stimuli, for example, a few degrees of temperature increase. It is made of an aligned carbon nanotube (CNT) sheet covalently connected to a polymer layer in which dibenzocycloocta‐1,5‐diene (DBCOD) actuating units are oriented parallel to CNTs. Upon exposure to low‐energy thermal stimulation, coordinated submolecular‐level conformational changes of DBCODs result in macroscopic thermal contraction. This unique thermal contraction offers distinct advantages. It's inherently fast, repeatable, low‐energy driven, and medium independent. The covalent interface and reversible nature of the conformational change bestow this bilayer with excellent repeatability, up to at least 70 000 cycles. Unlike conventional CNT bilayer systems, this system can achieve high precision actuation readily and can be scaled down to nanoscale. A new platform made of poly(vinylidene fluoride) (PVDF) in tandem with the bilayer can harvest low‐grade thermal energy and convert it into electricity. The platform produces 86 times greater energy than PVDF alone upon exposure to 6 °C thermal fluctuations above room temperature. This platform provides a pathway to low‐grade thermal energy harvesting. It also enables low‐energy driven thermal artificial robotics, ultrasensitive thermal sensors, and remote controlled near infrared (NIR) driven actuators.

In this work, nanoporous, heteroatom‐doped carbon materials with tailorable structures and excellent charge/energy storage properties are synthesized using casein (a phosphoprotein) as a precursor and silica gel as a template via a facile synthetic route. The synthesis involves carbonization and etching. In the synthesis, an appreciable amount of the N and P atoms in casein make it as dopants into the nanoporous carbons, enabling the materials to efficiently store charge. The structures and compositions as well as the overall charge storage properties of the materials are easily tuned by varying the relative amount of silica gel template used with casein in the precursors. By using an optimal amount of silica in the casein/silica self‐assemblies, a nanoporous carbon with low resistance to Faradaic processes and good capacitance and pseudocapacitance is obtained. This material gives a capacitance ofca. 261 F g⁻¹at 1 A g⁻¹, which is higher than those of many recently reported carbon materials in the literature. Moreover, the material retains 95 % of the initial capacitance withca. 100 % of coulombic efficiency after 10,000 charge‐discharge cycles.