Zhenan Bao

Block copolymers (BCPs) can spontaneously self-assemble into various nanostructured morphologies which enable their diverse applications in selective membranes, polymer electrolytes, and optoelectronics. To expand the range of nanostructures accessible to block copolymers, we designed dynamic block copolymers (DBCPs) that combine the phase separation of traditional block copolymers with the supramolecular self-assembly of periodic dynamic polymers. We demonstrate that DBCPs synthesized with a periodic block sequence self-assemble into high aspect ratio supramolecular nanofibers with well-ordered PEG and PDMS domains, in contrast to those synthesized with a random sequence which do not form nanofibers but have disordered morphologies. The periodicity of the block sequence ensures regular placement of dynamic bonds along the polymer chain, which enables stacking of the hydrogen …

An anode includes:(1) a current collector; and (2) an interfacial layer disposed over the current collector. The interfacial layer includes an ion-conductive organic network including anionic coordination units, organic linkers bonded through the anionic coordination units, and counterions dispersed in the ion-conductive organic network.

Aspects of various embodiments are directed to sensor apparatuses and methods thereof. An example sensor apparatus includes a capacitor and sensor circuitry. The capacitor includes a first substrate having a first electrode, a second substrate having a second electrode, and a dielectric layer. The dielectric layer has a plurality of dielectric structures arranged in a pattern, the first and second electrode being separated by the dielectric layer and arranged with an overlapping area with respect to one another. The sensor circuitry is coupled to the capacitor and configured and arranged to detect normal and shear forces applied to the sensor apparatus based on changes in capacitance derived from changes in at least one of a distance between first and second electrodes and the overlapping area of the first and second electrodes.

Cell type-specific interfaces within living animals will be invaluable for achieving communication with identifiable cells over the long term, enabling applications across many scientific and medical fields. However, biological tissues exhibit complex and dynamic organization properties that pose serious challenges for chronic cell-specific interfacing. A new technology, combining chemistry and molecular biology, has emerged to address this challenge: genetically targeted chemical assembly (GTCA), in which specific cells are genetically programmed (even in wild-type or non-transgenic animals, including mammals) to chemically construct non-biological structures. Here, we discuss recent progress in genetically targeted construction of materials and outline opportunities that may expand the GTCA toolbox, including specific chemical processes involving novel monomers, catalysts and reaction regimes both de …

Taking flexible technology to a new level, intrinsically stretchable electronics enable new sensing capabilities by facilitating seamless integration of cyber-physical electronic systems with the human body. This is made possible by their superior mechanical characteristics that are capable of accommodating the dynamical movement and shape changes of soft biological tissues without asserting excessive constraints. While previous stretchable thin-film transistors (TFTs) could only operate at subkilohertz, our recent advancements in materials and fabrication processes have pushed stretchable TFT speed to the megahertz regime, rivaling that of the state-of-the-art flexible technologies. However, under deformation, significant change in device characteristics remains a major challenge that hinders circuit and system design for practical applications. In this study, we conduct a systematic analysis to identify the causes for the …

The Li-S battery is a promising next-generation battery chemistry that offers high energy density and low cost. The Li-S battery has a unique chemistry with intermediate sulphur species readily solvated in electrolytes, and understanding their implications is important from both practical and fundamental perspectives. In this study, we utilise the solvation free energy of electrolytes as a metric to formulate solvation-property relationships in various electrolytes and investigate their impact on the solvated lithium polysulphides. We find that solvation free energy influences Li-S battery voltage profile, lithium polysulphide solubility, Li-S battery cyclability and the Li metal anode; weaker solvation leads to lower 1st plateau voltage, higher 2nd plateau voltage, lower lithium polysulphide solubility, and superior cyclability of Li-S full cells and Li metal anodes. We believe that relationships delineated in this study can guide the …

Electrolytes using fluorinated solvents have proven effective in improving the cycling life of Li-metal batteries, by forming a robust solid–electrolyte interphase through decomposition of anion and fluorinated solvent molecules. Herein, we modulated the fluorination degree of ether-based electrolyte solvents to investigate their performance in Li-metal batteries. We tuned the fluorination degree by installing a monofluoro substituent on one ethoxy group of 1,2-diethoxyethane (DEE) and varying the fluorination degree on the other one, providing three fluorinated DEE solvent molecules (i.e., F1F0, F1F1 and F1F2) with a relatively low fluorination degree. All three electrolytes showed improved solvation strength and ionic conductivities compared with previous highly fluorinated DEE electrolytes while retaining good oxidative stability. A full cell test using the Li-metal anode and nickel-rich cathode revealed that a higher …

In article number 2302633, Hanul Moon, Seunghyup Yoo, and co-workers propose a porous polymer network partially filled with ionic gels to enable gradual electrical-double-layer modulation that can lead to flexible pressure sensors with high sensitivity over a wide range of pressure. The developed sensors are expected to contribute to a wide range of applications, from artificial skins requiring a subtle (below 1 kPa) to medium (1 to 100 kPa) pressure range to very high-pressure cases such as robotics in manufacturing or under-water environment.