Frasermcdaniel8363
Furthermore, we demonstrate the precise 3D printing of complex conducting structures from OECTs to centimeter-sized PEDOTNafion figurines and millimeter-thick 100-leg thermoelectric modules on textile substrates. Thus, our strategy opens up new possibilities for the design of conducting, all-polymer bulk structures and the development of wearable electronics and electronic textiles.Cryogenic electron microscopy (cryo-EM) is a powerful technique for determining structures of multiple conformational or compositional states of macromolecular assemblies involved in cellular processes. Recent technological developments have led to a leap in the resolution of many cryo-EM data sets, making atomic model building more common for data interpretation. We present a method for calculating differences between two cryo-EM maps or a map and a fitted atomic model. The proposed approach works by scaling the maps using amplitude matching in resolution shells. To account for variability in local resolution of cryo-EM data, we include a procedure for local amplitude scaling that enables appropriate scaling of local map contrast. The approach is implemented as a user-friendly tool in the CCP-EM software package. To obtain clean and interpretable differences, we propose a protocol involving steps to process the input maps and output differences. We demonstrate the utility of the method for identifying conformational and compositional differences including ligands. We also highlight the use of difference maps for evaluating atomic model fit in cryo-EM maps.Two-dimensional (2D) covalent organic frameworks (COFs) are promising metal-free materials for photocatalytic water splitting because of their high surface area and predictability to assemble various molecules with tunable electronic properties. Unfortunately, 2D COFs capable of visible-light-driven photocatalytic overall water splitting are rare, partly due to rigorous requirements to their band alignments and coexistence of catalytic sites for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, 12 2D nitrogen-linked COFs are designed based on first-principles calculations and topological assembly of molecular segments with catalytic activities toward either HER or OER, respectively. The electronic band structures calculated with HSE06 method indicate that 2D COFs are semiconductors with a widely tunable bandgap ranging from 1.92 to 3.23 eV. The positions of both conduction and valence band edges of nine 2D COFs match well with the chemical reaction potential of H2/H+ and O2/H2O, which are capable of photocatalytic overall water splitting. Of particular importance is that three of them based on 2,4,6-tris(4-methylphenyl)-1,3,5-triazine (TST) can split water into hydrogen and oxygen under visible light. Our results agree with respect to the literature, with three of them having been studied for photocatalytic HER or CO2 reduction. In addition, we further experimentally demonstrate that I-TST presents both HER and OER activity under visible light. Our findings present a route to design practical 2D COFs as metal-free and single-material photocatalysts for overall water splitting under visible light.A stretchable electronic skin (e-skin) requires a durable elastomeric matrix to serve in various conditions. Therefore, excellent and balanced properties such as elasticity, water proof capability, toughness, and self-healing are demanded. However, it is very difficult and often contradictory to optimize them at one time. Here, a polyurethane (BS-PU-3) containing a polydisperse hard segment, hydrophobic soft segment, and a dynamic disulfide bond was prepared by one-pot synthesis. Unlike the normal two-pot reaction, BS-PU-3 obtained through the one-pot method owned a higher density of self-healing points along the main chain and a faster self-healing speed, which reached 1.11 μm/min in a cut-through sample and recovered more than 93% of virgin mechanical properties in 6 h at room temperature. Moreover, a remarkable toughness of 27.5 MJ/m3 assures its durability as an e-skin matrix. Even with a 1 mm notch (half of the total width) on a standard dumbbell specimen, it could still bear the tensile strain up to 324% without any crack propagation. With polybutadiene as the soft segment, the shape, microstructure, and conductivity in BS-PU-3 and BS-PU-3-based stretchable electronics kept very stable after soaking in water for 3 days, proving the super waterproof property. An e-skin demo was constructed, and self-healing in pressure sensitivity, mechanical, and electrical properties were verified.The potential in a synaptic simulation for neuromorphic computation has revived the research interest of resistive random access memory (RRAM). However, novel applications require reliable multilevel resistive switching (RS), which still represents a challenge. We demonstrate in this work the achievement of reliable HfO2-based RRAM devices for synaptic simulation by performing the Al doping and the postdeposition annealing (PDA). Transmission electron microscopy and operando hard X-ray photoelectron spectroscopy results reveal the positive impact of Al doping on the formation of oxygen vacancies. Detailed I-V characterizations demonstrate that the 16.5% Al doping concentration leads to better RS properties of the device. In comparison with the other reported results based on HfO2 RRAM, our devices with 16.5% Al-doping and PDA at 450 °C show better reliable multilevel RS (∼20 levels) performance and an increased on/off ratio. The 16.5% AlHfO2 sample with PDA at 450 °C shows good potentiation/depression characteristics with low pulse width (10 μs) along with a good On/Off ratio (>1000), good data retention at room temperature, and high temperature and good program/erase endurance characteristics with a pulse width of 50 ns. The synapse features including potentiation, depression, and spike time-dependent plasticity were successfully achieved using optimized Al-HfO2 RRAM devices. Selleck Vactosertib Our results demonstrate the beneficial effects of Al doping and PDA on the enhancement of the performances of RRAM devices for the synaptic simulation in neuromorphic computing applications.