Adenosine phosphate (AP) molecules play an important role in energy storage and release in vivo and possess the ability of assembly into various functional materials in vitro. However, energy-related applications of AP-based assemblies have been rarely reported. Herein, for the first time, we explored the piezoelectric properties of AP-based assemblies for energy production. X-ray diffraction indicated that the numbers of high-energy phosphate groups and metal ions would change the intermolecular noncovalent interactions for adenosine monophosphate (AMP), adenosine diphosphate potassium complex (ADPK), and adenosine triphosphate sodium complex (ATPNa), resulting in different supramolecular stacking modes of the AP-based assemblies. Density functional theory (DFT) calculations proved that the maximum piezoelectric coefficients of AMP, ADPK, and ATPNa were 11.9, 26.1, and 44.5 pC/N, respectively. The gradually enhanced piezoelectric response was attributed to the improvement of supramolecular polarization and crystal asymmetry induced by the distinct stacking modes. The ATPNa crystal-based piezoelectric device produced open-circuit voltages of approximately 0.85 V when subjected to a 50 N mechanical force, maintaining good mechanical stability ≈6000 pressing-releasing cycles. Furthermore, ATPNa crystals could act as highly piezoelectrically sensitive components in sensing systems for monitoring human sitting postures and the impact of falling objects. This work constructs piezoelectric energy materials utilizing bioenergetic AP molecules through supramolecular assembly, providing inspiration for the development of innovative bioinspired piezoelectric materials.
Keywords: adenosine phosphate; assembly; molecular stacking; piezoelectric materials; supramolecular chemistry.