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This study was dedicated to the investigation of poly(vinylidene fluoride) (PVDF) micropillar arrays obtained by soft lithography followed by phase inversion at a low temperature. Reduced graphene oxide (rGO) was incorporated into the PVDF as a nucleating filler. The piezoelectric properties of the PVDF-rGO composite micropillars were explored via piezo-response force microscopy (PFM). Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) showed that α, β, and γ phases co-existed in all studied samples, with a predominance of the γ phase. The piezoresponse force microscopy (PFM) data provided the local piezoelectric response of the PVDF micropillars, which exhibited a temperature-induced downward dipole orientation in the pristine PVDF micropillars. The addition of rGO into the PVDF matrix resulted in a change in the preferred polarization direction, and the piezo-response phase angle changed from −120° to 20°–40°. The pristine PVDF and PVDF loaded with 0.1 wt % of rGO after low-temperature quenching were found to possess a piezoelectric response of 86 and 87 pm/V respectively, which are significantly higher than the |d33eff| in the case of imprinted PVDF 64 pm/V. Thus, the addition of rGO significantly affected the domain orientation (polarization) while quenching increased the piezoelectric response.

Multifunctional aerogels, with intriguing micro‐morphologies and macroscopic sizes, are fabricated for the first time from silk fibroin (SF) biopolymer extracted from Bombyx mori silkworm cocoon to optimize the adsorption performances of heavy metal ions and soluble organic pollutants. By a synergistic combination of approaches such as surface‐modification of SF with polyethyleneimine (PEI) and its hierarchical cryo‐assembly with graphene oxide into various macrostructures, namely core‐shell, composite, and Janus, series of millimetric aerogels (2–3 mm) with interesting center divergent honeycomb micro‐morphologies are prepared. In addition, cryo‐assembly assisted electro‐spraying of SF‐PEI led to obtaining micro‐aerogels (74 µm), possessing a wrinkled surface morphology with a high surface area. The aerogel beads exhibit superior adsorption capacities for Cu2+ (186.7 mg g−1, in 240 min) with a regeneration potential, but also for anionic dyes, for example, methylene orange (811.3 mg g−1) and organic solvents (1138 g g−1% for chloroform). The large adsorption capacities and fast adsorption kinetics of cations obtained by these aerogels are attributed to their impressive micro‐morphologies and small geometries, enabling rapid diffusion and cations uptake. Therefore, the sustainability, biodegradability, ease of fabrications, rapid, and reusable adsorption performance make aerogel beads of this study highly potent for multipollutant adsorption.