Current high-performance thermoelectric materials require elaborate doping and synthesis procedures,particularly in regardtothe artificial structure,and the underlying thermoelectric mechanisms are still poorly understood. Here,w e report that an atural chalcopyrite mineral, Cu 1+x Fe 1Àx S 2 , obtained from ad eep-sea hydrothermal vent can directly generate thermoelectricity.T he resistivity displayed an excellent semiconducting character,a nd al arge thermoelectric power and high power factor were found in the low xr egion. Notably,electron-magnon scattering and alarge effective mass was detected in this region, thus suggesting that the strong coupling of doped carriers and antiferromagnetic spins resulted in the natural enhancement of thermoelectric properties during mineralization reactions.T he present findings demonstrate the feasibility of thermoelectric energy generation and electron/hole carrier modulation with natural materials that are abundant in the Earths crust.

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tem. -Green single crystals of the title compound are hydrothermally prepared from aqueous solutions of Cu(NO3)2 and NH4H2PO4 (2:1 molar ratio, autoclave, 473 K, 150 h). Cu2PO4OH crystallizes in the orthorhombic space group Pnnm with Z = 4. The structure is built up from Cu2O6(OH)2 dimers of edge-sharing CuO4(OH) trigonal bipyramids and [Cu2O6(OH)2]∞ chains of edge-sharing CuO4(OH)2 octahedra. Magnetic measurements reveal that the compound is a spin-gap system with a spin gap of about 139 K. A spin dimer analysis shows that the magnetic structure of Cu2PO4OH can be described by an isolated square-spin cluster model whose spin exchange pathways do no include the structural dimer. -(BELIK*, A. A.; KOO, H.-J.; WHANGBO, M.-H.; TSUJII, N.; NAUMOV, P.; TAKAYAMA-MUROMACHI, E.; Inorg.

The size tunability and chemical versatility of nanostructures provide attractive engineering potential to realize an electron source of high brightness and spatial temporal coherence, which is a characteristic ever pursued by high resolution electron microscopy. (1-3) Regardless of the intensive research efforts, electron sources that have ever produced atomic resolution images are still limited to the conventional eld emitters based on a bulk W needle. It is due to the lack of fabrication precision for nanostructured sources, that is required to align a nanometric emission volume along a macroscopic emitter axis with sub-degree angular deviation. (4) In this work, we produced a LaB 6 nanowire electron source which was micro-engineered to ensure a highly collimated electron beam with perfect lateral and angular alignment.Such electron source was validated by installing in an aberration-corrected transmission electron microscope, where atomic resolution in both broad-beam and probe-forming modes were demonstrated at 60kV beam energy. The recorded un-monochromated 0.20eV electron energy loss spectroscopy (EELS) resolution, together with 20% probe forming e ciency and 0.4% probe current peak-to-peak noise ratio under a wide vacuum range, presented the unique advantages of nanotechnology and promised high performance low-cost electron beam instruments.

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