Functionalized graphene has been extensively studied with the aim of tailoring properties for gas sensors, superconductors, supercapacitors, nanoelectronics, and spintronics. A bottleneck is the capability to control the carrier type and density by doping. We demonstrate that a two-step process is an efficient way to dope graphene: create vacancies by high-energy atom/ion bombardment and fill these vacancies with desired dopants. Different elements (Pt, Co, and In) have been successfully doped in the single-atom form. The high binding energy of the metal-vacancy complex ensures its stability and is consistent with in situ observation by an aberration-corrected and monochromated transmission electron microscope.

All-solid-state lithium metal battery is the most promising next-generation energy storage device. However, the low ionic conductivity of solid electrolytes and high interfacial impedance with electrode are the main factors to limit the development of all-solid-state batteries. In this work, a low resistance-integrated all-solid-state battery is designed with excellent electrochemical performance that applies the polyethylene oxide (PEO) with lithium bis(trifluoromethylsulphonyl)imide as both binder of cathode and matrix of composite electrolyte embedded with Li 7 La 3 Zr 2 O 12 (LLZO) nanowires (PLLN). The PEO in cathode and PLLN are fused at high temperature to form an integrated all-solid-state battery structure, which effectively strengthens the interface compatibility and stability between cathode and PLLN to guarantee high efficient ion transportation during long cycling. The LLZO nanowires uniformly distributed in PLLN can increase the ionic conductivity and mechanical strength of composite electrolyte efficiently, which induces the uniform deposition of lithium metal, thereby suppressing the lithium dendrite growth. The Li symmetric cells using PLLN can stably cycle for 1000 h without short circuit at 60 °C. The integrated LiFePO 4 /PLLN/Li batteries show excellent cycling stability at both 60 and 45 °C. The study proposed a novel and robust battery structure with outstanding electrochemical properties.

We have generated Dissociation (Ds) element insertions throughout the Arabidopsis genome as a means of random mutagenesis. Here, we present the molecular analysis of genomic sequences that flank the Ds insertions of 931 independent transposant lines. Flanking sequences from 511 lines proved to be identical or homologous to DNA or protein sequences in public databases, and disruptions within known or putative genes were indicated for 354 lines. Because a significant portion (45%) of the insertions occurred within sequences defined by GenBank BAC and P1 clones, we were able to assess the distribution of Ds insertions throughout the genome. We discovered a significant preference for Ds transposition to the regions adjacent to nucleolus organizer regions on chromosomes 2 and 4. Otherwise, the mapped insertions appeared to be evenly dispersed throughout the genome. For any given gene, insertions preferentially occurred at the 5' end, although disruption was clearly possible at any intragenic position. The insertion sites of >500 lines that could be characterized by reference to public databases are presented in a tabular format at http://www.plantcell. org/cgi/content/full/11/12/2263/DC1. This database should be of value to researchers using reverse genetics approaches to determine gene function.

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Oil-dispersible α-NaYF4 spherical nanoparticles and β-NaYF4 hexagonal-shaped nanoplates were synthesized by the liquid−solid two-phase approach at different reaction temperatures. The TEM and FE-SEM images reveal that the nanoplates have a relatively narrow size distribution. In comparison with other methods, pure β-NaYF4 hexagonal-shaped nanoplates were prepared under a relatively mild condition. The nanoplates grew at the liquid−solid interface with slow crystallization rate, which may be preferable for achieving β-NaYF4.

Interaction between single noble metal atoms and graphene edges has been investigated via aberration-corrected and monochromated transmission electron microscopy. A collective motion of the Au atom and the nearby carbon atoms is observed in transition between energy-favorable configurations. Most trapping and detrapping processes are assisted by the dangling carbon atoms, which are more susceptible to knock-on displacements by electron irradiation. Thermal energy is lower than the activation barriers in transition among different energy-favorable configurations, which suggests electron-beam irradiation can be an efficient way of engineering the graphene edge with metal atoms.

Flexible actuators responsive to multiple stimuli are much desired in wearable electronics. However, general designs containing organic materials are usually subject to slow response and limited lifetime, or high triggering threshold. In this study, we develop flexible, all-inorganic actuators based on bimorph structures composed of vanadium dioxide (VO) and carbon nanotube (CNT) thin films. The drastic, reversible phase transition of VO drives the actuators to deliver giant amplitude, fast response up to ∼100 Hz, and long lifetime more than 1 000 000 actuation cycles. The excellent electrical conductivity and light absorption of CNT thin films enable the actuators to be highly responsive to multiple stimuli including light, electric, and heat. The power consumption of the actuators can be much reduced by doping VO to lower its phase transition temperature. These flexible bimorph actuators find applications in biomimetic inspect wings, millimeter-scale fingers, and physiological-temperature driven switches.

The unique correspondence between mathematical operators and photonic elements in wave optics enables quantitative analysis of light manipulation with individual optical devices. Phase-transition materials are able to provide real-time reconfigurability of these devices, which would create new optical functionalities via (re)compilation of photonic operators, as those achieved in other fields such as field-programmable gate arrays (FPGA). Here, by exploiting the hysteretic phase transition of vanadium dioxide, an all-solid, rewritable metacanvas on which nearly arbitrary photonic devices can be rapidly and repeatedly written and erased is presented. The writing is performed with a low-power laser and the entire process stays below 90 °C. Using the metacanvas, dynamic manipulation of optical waves is demonstrated for light propagation, polarization, and reconstruction. The metacanvas supports physical (re)compilation of photonic operators akin to that of FPGA, opening up possibilities where photonic elements can be field programmed to deliver complex, system-level functionalities.