Publikationen

Highly conductive metal selenides have drawn increasing attention in the field of energy storage. Unfortunately, their application is severely limited by the inferior capacity contribution as well as unsatisfactory cycling stability. Here, we propose a simple and practical way to prepare hollow nickel-cobalt-manganese selenides (NCMSe) submicrospheres. The NCMSe submicrospheres exhibit rich redox reactions during the reaction process into which much more alkali metal ions can be inserted, leading to high reversible capacity and their hollow structure facilitates the contact between the active material and electrolyte to accelerate the redox kinetics. Benefiting from these features, the hollow NCMSe submicrospheres show superior Li-storage capacity (1600 mAh g^-1 after 1000 cycles at 2 A g^-1) and Na-storage capacity (695 mAh g^-1 after 200 cycles at 0.1 A g^-1). This work offers a novel insight to the remarkable electrochemical performance anode materials for both lithium and sodium ion batteries.

We report the design and optimized fabrication of deformed whispering gallery mode resonators in silica with solely ICP-RIE. This allows us to control the morphology of the resonators more freely and results in low surface roughness. The light was coupled into the resonator using a state of the art tapered fiber approach and we determined the Q-factor in the range of 10^5

Three-dimensional (3D) flexible surface enhanced Raman scattering (SERS) substrates of silver nanoparticles (Ag-NPs) decorated Germanium nanowhiskers (Ge-NWHKs) grafted on carbon fiber cloth (CFC) (denoted as Ag-NPsGe-NWHKs@CFC) are constructed via chemical vapor deposition growth of high-density Ge-NWHKs on CFC and then assembly of Ag-NPs on the Ge-NWHKs by galvanic displacement. Ordered 3D framework of Ge-NWHKs grafted flexible CFC impels the formation of large amounts of Ag-NPs with homogenous distribution via spontaneous reduction of Ag+ ions. Thus, the Ag-NPs@Ge-NWHKs@CFC SERS substrates present ultra-high sensitivity, good reproducibility, and high flexibility. This SERS sensor has achieved a detection limit of 1 pM for Rhodamine 6G and 0.1 nM for thiram respectively. The as-fabricated SERS substrates show promising potential for applications in rapid detection of trace organic pollutants in the aquatic environment.