No abstract

With the rapid development of flexible electronics, the demand for flexible electromagnetic interference (EMI) shielding materials is increasing. This study develops a new green and effective strategy, consisting of graphene oxide (GO) and cellulose nanofibrils (CNF) co‐stabilized Pickering emulsion combined with hot‐pressing technology, to prepare flexible and conductive nitrile rubber (NBR) composite films. The composite films consist of a 3D network conductive skeleton structure of reduced GO (RGO) and an isolated NBR structure. This specific design results in a maximum high conductivity of 99 S m−1, which is higher by an order of magnitude compared with that of the composites obtained using the traditional solution blending method, and a stable EMI shielding effectiveness of 25.81 dB in the X band. The introduction of the flexible NBR results in the excellent flexibility and structural strength of the composite film, and exhibits a decrease of 2.51% in the EMI shielding efficacy after 5000 cycles. As a piezoresistive sensor for wearable devices, the CNF‐RGO/NBR flexible film can hold precise current signals and respond to finger motion. The findings of this study can provide new insights for the design of conductive and flexible composites as wearable and portable medical equipment and electronic devices.

Interface design is an efficient way to improve the steam generation performance of solar evaporators. Accompanied with the formation of cellulose nanofiber/polylactic acid/polyaniline (PANI) hybrid aerogel (HA) by Pickering emulsion and in situ polymerization, this paper proposes a new perspective of hierarchical interface design strategy to accelerate the water evaporation driven by solar energy. By changing the concentration and type of doped acid, the distribution gap of different PANI forms in HA can be microscopically designed. PANI nanoclusters with smaller gaps facilitate HA to achieve an improved light absorption, photothermal conversion capability and steam generation rate. Moreover, macro interface design introduces hemispherical depression structures to the HA surface through a simple mold. These recessed surfaces not only increase the light absorption by increasing the multiple reflections and refractions of light on the recesses, but also recover part of the heat radiation loss to the environment. A higher evaporation rate of 1.65 kg m−2 h−1 with a steam generation efficiency of 94.6% is achieved under the irradiation of 1 Sun (100 mw cm−2). Finally, HAs have strong purification ability for various raw water, and are promising in terms of their application potential in the field of energy conversion.

The unique C-rGO/Fe3O4 carbon foam with hollow microsphere and concave–convex microstructure had excellent EMW absorption performance with smart function-tunable feature, also showing potential application for monitoring humans’ physiological signal.

No abstract