a | Theoretical and experimental approaches for the rational design of nanofibrillar materials. b | Multiscale material design strategy. c | Material-by-design paradigm. AFM, atomic force microscopy; CryoEM, cryoelectron microscopy; DFT, density functional theory; EPR, electron paramagnetic resonance; FTIR, Fourier transform infrared spectroscopy; MD, material design; MEMS, microelectromechanical systems; QM, quantum mechanics; TEM, transmission electron microscopy; TRSTM, thermal radiation scanning tunnelling microscopy; XRD, X-ray diffraction.