Jingdezhen Ceramic Institute

About: Jingdezhen Ceramic Institute is a education organization based out in Jingdezhen, China. It is known for research contribution in the topics: Ceramic & Dielectric. The organization has 1766 authors who have published 1781 publications receiving 20250 citations.

Amorphous Metallic NiFeP: A Conductive Bulk Material Achieving High Activity for Oxygen Evolution Reaction in Both Alkaline and Acidic Media

Abstract: The intrinsic catalytic activity at 10 mA cm-2 for oxygen evolution reaction (OER) is currently working out at overpotentials higher than 320 mV. A highly efficient electrocatalyst should possess both active sites and high conductivity; however, the loading of powder catalysts on electrodes may often suffer from the large resistance between catalysts and current collectors. This work reports a class of bulk amorphous NiFeP materials with metallic bonds from the viewpoint of electrode design. The materials reported here perfectly combine high macroscopic conductivity with surface active sites, and can be directly used as the electrodes with active sites toward high OER activity in both alkaline and acidic electrolytes. Specifically, a low overpotential of 219 mV is achieved at the geometric current density 10 mA cm-2 in an alkaline electrolyte, with the Tafel slope of 32 mV dec-1 and intrinsic overpotential of 280 mV. Meanwhile, an overpotential of 540 mV at 10 mA cm-2 is attained in an acidic electrolyte and stable for over 30 h, which is the best OER performance in both alkaline and acidic media. This work provides a different angle for the design of high-performance OER electrocatalysts and facilitates the device applications of electrocatalysts.

Evaluation of Structural Characteristics of Huadian Oil Shale Kerogen Using Direct Techniques (Solid-State 13C NMR, XPS, FT-IR, and XRD)

Abstract: A sample of kerogen isolated from Huadian oil shale was studied using a combination of solid-state 13C NMR, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), and X-ray diffraction (XRD) techniques to evaluate its structural characteristics. 13C NMR results indicate that the carbon skeletal structure of this kerogen is mainly composed of a fairly high fraction of aliphatic carbon (86.1%), with a very low aromaticity (fa) of 9.7%; methylene (CH2) carbons dominate in all types of aliphatic carbons and the majority of them exist as many long straight chains but not saturated alicyclics. The average methylene carbon chain length (Cn) is between 12 and 24. There are only one fused aromatic ring (e.g., naphthalene) or two single aromatic rings (one benzene ring and one penta-heterocycle) per 100 carbon atoms. However, aromatic rings in this kerogen have a very high value of substitutive degree (δ = 0.42–0.75). Furthermore, XRD analysis suggests that most methylene straight chains and ar...

Improved Thermoelectric Performance of Silver Nanoparticles‐Dispersed Bi2Te3 Composites Deriving from Hierarchical Two‐Phased Heterostructure

Abstract: A practical and feasible bottom-up chemistry approach is demonstrated to dramatically enhance thermoelectric properties of the Bi2Te3 matrix by means of exotically introducing silver nanoparticles (AgNPs) for constructing thermoelectric composites with the hierarchical two-phased heterostructure. By regulating the content of AgNPs and fine-tuning the architecture of nanostructured thermoelectric materials, more heat-carrying phonons covering the broad phonon mean free path distribution range can be scattered. The results show that the uniformly dispersed AgNPs not only effectively suppress the growth of Bi2Te3 grains, but also introduce nanoscale precipitates and form new interfaces with the Bi2Te3 matrix, resulting in a hierarchical two-phased heterostructure, which causes intense scattering of phonons with multiscale mean free paths, and therefore significantly reduce the lattice thermal conductivity. Meanwhile, the improved power factor is maintained due to low-energy electron filtering and excellent electrical transport property of Ag itself. Consequently, the maximum ZT is amazingly found to be enhanced by 304% arising from the hierarchical heterostructure when the AgNPs content reaches 2.0 vol%. This study offers an easily scalable and low-cost route to construct a wide range of multiscale hierarchically heterostructured bulk composites with significant enhancement of thermoelectric performance.