MXenes are an emerging class of 2D transition metal carbides and nitrides. They have been widely used in flexible electronics owing to their excellent conductivity, mechanical flexibility, and water dispersibility. In this study, the electrode and active layer applications of MXene materials in electronic skins are realized. By utilizing vacuum filtration technology, few‐layer MXene electrodes are integrated onto the top and bottom surfaces of the 3D polyacrylonitrile (PAN) network to form a stable electronic skin. The fabricated flexible device with Ti3C2Tx MXene electrodes outperforms those with other electrodes and exhibits excellent device performance, with a high sensitivity of 104.0 kPa−1, fast response/recovery time of 30/20 ms, and a low detection limit of 1.5 Pa. Furthermore, the electrode and the constructed MXene/PAN‐based flexible pressure sensor exhibit robust mechanical stability and can survive 240 bending cycles. Such a robust, flexible device can be enlarged or folded like a jigsaw puzzle or origami and transformed from 2D to 3D structures; moreover, it can detect tiny movements of human muscles, such as movements corresponding to sound production and intense movements during bending of fingers.

Performance of thin film photovoltaics largely relies on photon absorption capability. Here, we introduce a novel substrate with patterned aluminum nanodent arrays with unique light management capability. Hydrogenated amorphous silicon thin film solar cells have been fabricated on the nano-texturized substrate for optical property study and photovoltaic performance evaluation. Our measurements have shown significant enhancement on broadband light absorption using these patterned substrates via both geometrical light trapping and plasmonic coupling. Particularly, the enhancement factor reaches as high as 5-30 times at wavelength near the band edge. Numerical simulations confirm the measurements and uncover the mechanisms of the enhancement. More importantly, photovoltaic measurements on nanodent solar cells present improvements of over 31% and 27% in short circuit current and energy conversion efficiency respectively compared with planar solar cells. Therefore, the novel patterned substrates are promising candidates for low cost and high performance thin film solar cells. Broader contextAmong various alternative energy sources, solar power is of great advantage over other candidates due to its abundance and environmental friendliness. Current solar cells still cannot satisfy people's expectation on performance and cost. Aiming at promoting the ability of harvesting solar power as well as reducing the manufacturing cost, a novel plasmonic substrate was developed using a convenient anodization method for thin lm amorphous silicon solar cells, which convert solar power into electricity within a very thin absorbing layer. According to experimental and nite-difference time-domain simulations, the devices exhibit impressive light trapping capability, due to the coupling of waveguide modes and surface plasmon resonances with the aid of nanoscale patterns. The optimized device conguration delivered 5-30 times absorption enhancement near the band edge. The optical absorption and propagation were systematically investigated in view of photonic guided modes and surface plasmon resonances as well as their coupling effects. In comparison to the device on planar substrates, the plasmonic solar cells achieved signicantly increased short circuit current (31%) with a promising energy conversion efficiency up to 7.11%.

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Bit commitment is a fundamental cryptographic task that guarantees a secure commitment between two mutually mistrustful parties and is a building block for many cryptographic primitives, including coin tossing 1, 2 , zero-knowledge proofs 3, 4 , oblivious transfer 5, 6 and secure two-party computation 7 . Unconditionally secure bit commitment was thought to be impossible 8-13 until recent theoretical protocols that combine quantum mechanics and relativity were shown to elude previous impossibility proofs 14-17 . Here we implement such a bit commitment protocol 17 . In the experiment, the committer performs quantum measurements using two quantum key distribution systems 18 and the results are transmitted via free-space optical communication to two agents separated with more 1