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Bilayer actuators, traditionally consisting of two laminated materials, are the most common types of soft or hybrid actuators. Herein, a nanomaterial‐based organic–inorganic humidity‐sensitive bilayer actuator composed of TEMPO‐oxidized cellulose nanofibrils (TCNF‐Na+) and reduced graphene oxide (rGO) sheets is presented. The hybrid actuator displays a large humidity‐driven locomotion with an atypical fast unbending. Cationic exchange of the anionically charged TCNF‐Na+ and control of the layer thickness is used to tune and dictate the locomotion and actuator's response to humidity variations. Assembly of a self‐oscillating electrical circuit, that includes a conductive rGO layer, displays autonomous on‐and‐off lighting in response to actuation‐driven alternating electrical heating. [ABSTRACT FROM AUTHOR]

Highly porous and hyper‐cross‐linked polymers (HCPs) have a range of applications and are typically synthesized in an unsustainable manner. Herein, HCPs were synthesized from abundant biobased or biorelated compounds in sulfolane with iron(III) chloride as Lewis acid catalyst. As reactants, quercetin, tannic acid, phenol, 1,4‐dimethoxybenzene, glucose, and a commercial bark extract were used. The HCPs had high CO2 uptake (up to 3.94 mmol g−1 at 0 °C and 1 bar), total pore volumes (up to 1.86 cm3 g−1), and specific surface areas (up to 1440 m2 g−1). 1H NMR, 13C NMR, and IR spectroscopy, wide‐angle X‐ray scattering, elemental analysis, and SEM revealed, for example, that the HCPs consisted of amorphous and cross‐linked aromatic and phenolic structures with significant contents of aliphatics, oxygen, and sulfur. Greener HCPs: A wide range of biomass‐based aromatic compounds are used as precursors for highly porous hyper‐cross‐linked polymers (HCPs) in a sustainable synthesis system. The HCPs have large pore volumes and high CO2 uptakes, which are useful in sustainability‐related applications. [ABSTRACT FROM AUTHOR]