Pressure sensing is an important function of electronic skin devices. The development of pressure sensors that can mimic and surpass the subtle pressure sensing properties of natural skin requires the rational design of materials and devices. Here we present an ultrasensitive resistive pressure sensor based on an elastic, microstructured conducting polymer thin film. The elastic microstructured film is prepared from a polypyrrole hydrogel using a multiphase reaction that produced a hollow-sphere microstructure that endows polypyrrole with structure-derived elasticity and a low effective elastic modulus. The contact area between the microstructured thin film and the electrodes increases with the application of pressure, enabling the device to detect low pressures with ultra-high sensitivity. Our pressure sensor based on an elastic microstructured thin film enables the detection of pressures of less than 1 Pa and exhibits a short response time, good reproducibility, excellent cycling stability and temperature-stable sensing.

An artificial solid electrolyte interphase (SEI) is demonstrated for the efficient and safe operation of a lithium metal anode. Composed of lithium-ion-conducting inorganic nanoparticles within a flexible polymer binder matrix, the rationally designed artificial SEI not only mechanically suppresses lithium dendrite formation but also promotes homogeneous lithium-ion flux, significantly enhancing the efficiency and cycle life of the lithium metal anode.

developed low-cost active PV material. [1][2][3][4][5] To fulfill this promise, perovskites must first overcome the chemi cal [6][7][8] and thermomechanical instability [9] that has long been observed in them. Recent efforts have demonstrated progress in improving the chemical stability of perovskite devices intrinsically by tuning cation composition [10,11] and extrinsically by encapsulation. [12][13][14][15] However, the perovskite field has demonstrated insouciance toward thermomechanical stability, even though it is essential for the commercialization of photovoltaic cells or lightemitting diodes. While some promising results have recently been achieved in scalability with power conversion efficiencies (PCE) of 12% for 100 cm 2 perovskite devices, [16] the thermomechanical instability of perovskites remains a significant challenge to producing module-scale perovskite solar cells [17] with operational lifetimes comparable to c-Si and CdTe. [18] In particular, stresses are generated in perovskite films during processing and magnified in service by environmental effects such as thermal cycling, resulting in the formation of defects and propagation of fracture and delamination. [19] Additionally, cracks that develop in the film are a source of accelerated degradation for the transport of gases, moisture, and other environmental species. Unfortunately, perovskite layers are exceptionally fragile and susceptible to delamination as measured by their fracture energy [20,21] -less robust than organic photovoltaics (OPVs) by an order of magnitude [22] and c-Si or copper indium gallium diselenide (CIGS) solar cells by two orders of magnitude. [9] Despite the significance of film stresses for device stability, the origin and magnitude of stresses in perovskite films have been largely overlooked. In addition to causing fracture, stress accelerates the rate of photochemical degradation in many materials-such as fuel cell membranes, [23] laser diodes, [24] and encapsulants [25] -and a recent report shows that perovskite are no exception. [26] Perovskites can accumulate residual stresses during processing through several pathways. For example, in solar cell devices, perovskites have much higher coefficients of thermal expansion (CTE) than the other device layers and the glass substrate. [27] When perovskites are annealed after deposition and subsequently cooled back to room temperature, a lower-CTE substrate constrains the An overlooked factor affecting stability: the residual stresses in perovskite films, which are tensile and can exceed 50 MPa in magnitude, a value high enough to deform copper, is reported. These stresses provide a significant driving force for fracture. Films are shown to be more unstable under tensile stress-and conversely more stable under compressive stresswhen exposed to heat or humidity. Increasing the formation temperature of perovskite films directly correlates with larger residual stresses, a result of the high thermal expansion coefficient of perovskites. Specifically, this tensile stress forms u...

High-energy all-solid-state lithium (Li) batteries have great potential as next-generation energy storage devices. Among all choices of electrolytes, polymer-based systems have attracted wide-spread attention due to their low density, low cost, and excellent processability. However, they are generally mechanically too weak to effectively suppress Li dendrites and have lower ionic conductivity for reasonable kinetics at ambient temperature.Herein, an ultra-strong reinforced composite polymer electrolyte (CPE) has been successfully designed and fabricated by introducing a stiff mesoporous SiO 2 aerogel as the backbone for a polymer-based electrolyte. The interconnected SiO 2 aerogel not only perform as a strong backbone strengthening the whole composite, but also offer large and continuous surfaces for strong anion adsorption, which produces a highly-conductive pathway across the composite.As a consequence, a high modulus of ~0.43 GPa and high ionic conductivity of ~0.6 mS cm -1

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