3 results about "Te element" patented technology

The application relates to a high-performance n-type bismuth telluride-based thermoelectric material and a preparation method thereof, and belongs to the technical field of thermoelectric conversion. The chemical composition of the n-type bismuth telluride-based thermoelectric material is La y Bi 2‑ y Te 2.7 Se 0.3 -xwt%Te, 0<=x<=1.5, 0<=y<=0.015, x and y are not 0 at the same time. Under the premise of fixing the Se doping amount, the application reduces the Te element to increase Te vacancies, reduces the carrier concentration, moves the dimensionless thermoelectric optimization value zT peak to the low-temperature direction, simultaneously utilizes La-doped Bi to optimize the electrothermal transport performance, and finally realizes the obvious improvement of the zT value.

The invention discloses a tellurium element modified cobalt-free lithium-rich manganese-based positive electrode material and a preparation method thereof, and belongs to the technical field of lithium ion battery materials. According to the method, Te and a lithium-rich manganese-based positive electrode material are subjected to solid-phase mixing, calcination, further annealing and surface doping on the material so as to obtain the modified LLR-Te material. The Te element of the template is doped in a gradient manner to form a strong Te-O covalent bond, so that phase change is inhibited, a lattice frame is stabilized, the structure is stabilized under high voltage, and the electrochemical stability is maintained; and meanwhile, an interface modification layer is constructed on the surface of the material in situ, electrolyte erosion is blocked through chemical bonding, and transition metal dissolution is inhibited. According to the method, the structural stability, the cycle life and the rate capability of the material under the high voltage of 4.8 V are remarkably improved. The modified material disclosed by the invention shows excellent high-voltage compatibility in a liquid / solid-state battery system, and an innovative solution is provided for a positive electrode material of a high-energy-density lithium ion battery.

The invention relates to a Cu-Te / ZnO (at) Gr composite material and a preparation method thereof. The preparation method comprises the following steps: step 1, pre-alloying copper and tellurium; step 2, supersonic gas atomization powder preparation; 3, zinc oxide in-situ growth, wherein the surface of the Cu-Te pre-alloyed powder obliquely grows and is coated with a ZnO nanoneedle array; 4, antioxidant composite treatment is conducted, specifically, the ZnO-coated Cu-Te powder prepared in the step 3 is soaked in an ethanol solution containing 0.8 wt% of an organic borosilicate complexing agent; and step 5, chemically bonding graphene, and treating by adopting a pH response type graphene oxide dispersion liquid. By adopting the technical scheme, the obliquely growing ZnO nanoneedle transition layer and the graphene shell layer are constructed to synergistically form a three-dimensional anchoring structure, chemical bonding with graphene is enhanced, and on the basis of the low-temperature in-situ reaction of the zinc-ammonium complexing solution and the synergistic effect of the organic boron-silicon complexing agent, a compact glass phase is formed at a high temperature, so that the performance of the composite material is improved. The volatilization rate of the Te element is reduced, and a Si-O-Zn covalent bond is formed between ZnO and graphene in combination with three-stage pH regulation.