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The new inorganic material known as "high-entropy oxides" (HEOs) has a single-phase structure and is made up of several different main metal elements. It has many useful properties, including a high specific capacity, excellent cycling performance, high structural stability, and super-electronic conductivity. For lithium-ion batteries, it is viewed as a promising electrode material (LIBs). It is significant to develop high entropy oxides with different components and study their properties. Herein, Mg, Ni and Li are added to the quaternary medium entropy (CrFeMnCo)3O4. Four new spinel high entropy oxides were synthesized by glycine-nitrate SCS method at 750 °C and their material characterization and electrochemical properties were investigated respectively. The experimental results show that the four obtained samples have uniform particle size distribution. As for the electrochemical test, the capacities of the (CrFeMnCoMg)3O4 and (CrFeMnCoNi)3O4 do not decrease significantly after 800 cycles at 2000 mA·g−1. They have better cycle stability than the (CrFeMnCoMgLi)3O4 and (CrFeMnCoNiLi)3O4. As the anode of LIBs, all HEOs show excellent cycle stability and rate capability. This work provides a new strategy for designing high-entropy energy storage materials. [ABSTRACT FROM AUTHOR]

Compared to 1D compressed sensing (CS), 2D CS is more efficient for compressing the plaintext image from two directions, but security level of current 2D CS-based ciphers is unsatisfactory. To solve this problem, this paper presents a novel color image compression and encryption algorithm by combining 2D CS, information entropy and chaos. Firstly, the color image is decomposed into red, green and blue components, then they are sparsely transformed by the discrete wavelet transform (DWT) to get three sparse matrices. Next, the obtained matrices are observed by two asymptotical deterministic random measurement matrices based on information entropy and counter (ADMMIC), which not only encrypts the plaintext image, but also compresses it in proportion to reduce the transmission bandwidth and storage space. Subsequently, the corresponding measurement value matrices are shuffled by a double random scrambling based on Arnold map and index vector (DRSAIV) to eliminate the correlation between adjacent pixels. Furthermore, the obtained permutated matrices are diffused by a simultaneous multiple random diffusion of inter–intra components (SMRDIC) to obtain the final cipher image, the plaintext pixel to be diffused, the key matrix involved in diffusion and the position of the obtained ciphertext pixel are all unpredictable, which makes statistical attack invalid. In addition, information entropy values of plaintext image are obtained to generate the initial values of the used chaotic systems, which greatly improve the ability to resist the known-plaintext and chosen-plaintext attacks. Simulation results and security analyses verify that this algorithm has good compression and high security. [ABSTRACT FROM AUTHOR]

In this work, we synthesized K2Ti6O13 nanowires coated with sulfur-doped carbon for the first time, with fulvic acid and cystine as the carbon source, which exhibit higher capacity and rate performance compared with pure potassium titanate. Via analyzing the cyclic voltammetry curves obtained at different scan rates, it is revealed that the capacity increase is due to the improved ion diffusivity induced by the carbon coating. Moreover, cystine is demonstrated to be a better carbon source than fulvic acid. [ABSTRACT FROM AUTHOR]