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Chalcopyrite (CuFeS2) is a widespread natural mineral, composed of earth-abundant and nontoxic elements. It has been considered a promising n-type material for thermoelectric applications. In this work, a series of Zn-doped Cu1- xZn xFeS2 ( x = 0-0.1) compounds are synthesized by vacuum melting combined with the plasma activated sintering process. The role of Zn in the chalcopyrite and its different effects on thermoelectric properties, depending on its concentration and location in the crystal lattice, are discussed. It is found that Zn is an effective donor which increases the carrier concentration and improves the thermoelectric properties of CuFeS2. When the content of Zn exceeds the solubility limit, Zn partially enters the Cu sites and forms in situ ZnS nanophase. This, in turn, shifts the balance between the anion and cation species which is re-established by the formation of antisite Fe/Cu defects. Beyond maintaining charge neutrality of the structure, such antisite defects relieve the lattice strain in the matrix and increase the solubility of Zn further. The highest ZT value of 0.26 is achieved at 630 K for Cu0.92Zn0.08FeS2, which represents an enhancement of about 80% over that of the pristine CuFeS2 sample. [ABSTRACT FROM AUTHOR]

In this paper, an exceptional nitrate reduction to ammonia catalyst is reported, enabled by BO2− anion induction effects combining heterogeneous branching architecture‐driven mass transport enhancement strategies. The implantation of the BO2− anion can inductively enhance the electron cloud density and electron transmission paths of intrinsic catalysts, makes electron more active to improve the conductivity, regulates the adsorption and desorption rates of intermediates by space barrier effect, reduces the binding energy of the electron and 3d orbital of Ni in NiFe(BO2)O(OH), thereby lowing the transform free energy of the determining *NO3 to *HNO3 step. 3D hollow sea urchin lattice heterogeneous branching structure can self‐drive generate differentiated micro convection intervals, which will be beneficial for improving mass transfer dynamics especially localized disturbance mass transfer effect of catalyst for nitrate reduction reaction (NO3RR) catalysis process. Amazingly, the as‐prepared 3D NiFe metaborate oxyhydroxide hollow bionic sea urchins lattice catalyst has a high NH3 rate 6.27mmol·h−1·cm−2 with 98.7% Faradaic efficiency at low ‐0.25V(vs RHE) NO3RR potential. Moreover, the catalytic activity of this highly stable catalyst decreases only slightly over 100 h at ultra‐high 1500mA·cm−2 current. This work breaks through the bottleneck that plagues the performance improvement of non Cu‐based high‐current NO3RR catalysts. [ABSTRACT FROM AUTHOR]