The development of pressure sensors of high sensitivity and stable robustness over a broad range is indispensable for the future progress of electronic skin applicable to the detection of normal and shear pressures of various dynamic human motions. Herein, we present a flexible capacitive tactile sensing array that incorporates a porous dielectric layer with micro-patterned structures on the surface to enable the sensitive detection of normal and shear pressures. The proposed sensing array showed great pressure-sensing performance in the experiments, with a broad sensing range from several kPa to 150 kPa of normal pressure and 20 kPa of shear pressure. Sensitivities of 0.54%/kPa at 10 kPa and below, 0.45%/kPa between 10 kPa and 80 kPa, and 0.12%/kPa at 80 kPa and above were achieved for normal pressures. Meanwhile, for shear pressures, sensitivities up to 1.14%/kPa and 1.08%/kPa in x and y directions, respectively, and below 10 kPa, 0.73%/kPa, and 0.75%/kPa under shear pressure over 10 kPa were also validated. The performance of the finger-attached sensing array was also demonstrated, demonstrating which was a potential electronic skin to use in all kinds of wearable devices, including prosthetic hands, surgical robots, and other pressure monitoring systems.

The spills of crude oil and other organic chemicals are common around the world, resulting in severe damage to the environment and ecosystem. Therefore, developing low-cost and eco-friendly absorption material is in urgent need. In this study, we report a superhydrophobic and oleophilic porous material using biomass cuttlebone as the scaffold. A layer of polydopamine is grafted on the cuttlebone as the adhesion layer between the cuttlebone and the superhydrophobic coating. The in situ grown silica micro/nanoparticles on top of the adhesion layer provide the anchoring spots for grafting the fluorinated hydrocarbon and a rough topography for realizing superhydrophobicity. The static water contact angle of the superhydrophobic cuttlebone reaches 152°, and its oil contact angle is ~0°. The excellent oil–water separation efficiency of the prepared superhydrophobic cuttlebone is demonstrated using high-density oil/water mixtures and low-density oil/water mixtures.

Transparent cellulose papers used as substrates have gained increasing attention in the flexible optoelectronics field. However, significant challenges remain in overcoming the hydrophilicity of transparent cellulose papers and endowing them with conductivity for multifunctional applications. Herein, a new avenue for the construction of highly transparent, ionically conductive, and hydrophobic cellulose paper (HCP) via photopolymerization is reported. The photopolymerization of ionic liquid-containing photopolymerizable precursor and allyl cellulose on the surface of allyl cellulose paper yields robust functional surfaces. The obtained HCP displays high transparency (>90% in a wide wavelength range), better surface hydrophobicity (water contact angle ~127°), and high thermostability (onset thermal decomposition ~220 °C). In addition, the HCP exhibits reliable, sensitive and reproducible abilities to external stimulus. Significantly, the ionic conductive HCP has successfully been used for the construction of integrated and flexible optoelectronic devices. This promising strategy provides new insights into tailoring the surface hydrophobicity and functionality of cellulose paper for flexible electronic devices.