The single-phase oxides with elemental complexity and compositional diversity, usually named high entropy oxides, feature homogeneously dispersed multi-metallic elements in equiatomic concentration. The unusual properties of high entropy oxides endow their potential application in clean-energy-related electrocatalysis. However, the possible fundamental relationship between configuration entropy and the underlying catalytic mechanism is still not well understood and established. Herein, a high entropy perovskite cobaltate consisting of five equimolar metals in the B-site (Mg, Mn, Fe, Co, and Ni) is employed as an electrocatalyst for oxygen evolution reaction (OER). The configuration entropy serves as an effective tool to promote the intrinsic activity of the Co reactive site and manipulate the OER mechanism. The high entropy cobaltate demonstrates a lower overpotential of 320 mV at a current density of 10 mA cm −2 , outperforming other counterparts. The X-ray spectroscopies disclose the synergistic charge-exchange effect among different cations and the formation of a new oxygen hole state. Combinatorially computational and experimental results unveil the enigma that the high configuration entropy leads to the random occupation of cations, facilitates the surface reconstruction, and benefits the formation of stable surface oxygen vacancies. Owing to these merits, the O 2 formation is found to be kinetically favorable via the lattice oxygen mechanism.

The combination of ammonia fuel and proton‐conducting fuel cells (PCFCs) technology may provide an ideal clean energy system for the future, considering matured NH3 synthesis technology and transportation and storage infrastructure, the high energy density of NH3, and the high efficiency of fuel cells. However, poor catalytic activity of the anode for NH3 decomposition, quick performance degradation due to the ammonia induced nickel coarsening, difficult sintering, and insufficient proton conductivity of electrolytes are the main challenges for stable and high‐power generation from ammonia‐fueled PCFCs. Herein, a new Ba(Zr0.1Ce0.7Y0.1Yb0.1)0.95Pd0.05O3−δ perovskite is reported as a key anode component and electrolyte, which demonstrates multifunctionalities and tackles most challenges of conventional PCFCs. The incorporation of a small amount of Pd boosts catalytic activity of the nickel‐perovskite cermet anode for NH3 decomposition and increases proton conductivity from the creation of B‐site cation deficiency and electrolyte sintering. The corresponding thin‐film electrolyte PCFC delivers a maximum power density of 724 mW cm–2 at 650 °C operated on NH3, much higher than the similar cell without Pd incorporation (450 mW cm–2). Furthermore, no apparent performance decay is observed for the cell operated at 550 °C in H2 and NH3 for 350 h, making it highly promising for practical applications.

Reversible proton ceramic electrochemical cell (R-PCEC) is regarded as the most promising energy conversion device, which can realize efficient mutual conversion of electrical and chemical energy and to solve the problem of large-scale energy storage. However, the development of robust electrodes with high catalytic activity is the main bottleneck for the commercialization of R-PCECs. Here, a novel type of high-entropy perovskite oxide consisting of six equimolar metals in the A-site, Pr1/6La1/6Nd1/6Ba1/6Sr1/6Ca1/6CoO3−δ (PLNBSCC), is reported as a high-performance bifunctional air electrode for R-PCEC. By harnessing the unique functionalities of multiple elements, high-entropy perovskite oxide can be anticipated to accelerate reaction rates in both fuel cell and electrolysis modes. Especially, an R-PCEC utilizing the PLNBSCC air electrode achieves exceptional electrochemical performances, demonstrating a peak power density of 1.21 W cm−2 for the fuel cell, while simultaneously obtaining an astonishing current density of − 1.95 A cm−2 at an electrolysis voltage of 1.3 V and a temperature of 600 °C. The significantly enhanced electrochemical performance and durability of the PLNBSCC air electrode is attributed mainly to the high electrons/ions conductivity, fast hydration reactivity and high configurational entropy. This research explores to a new avenue to develop optimally active and stable air electrodes for R-PCECs.

Background/Aims: The pathogenesis of Lumbar disc degeneration (LDD) has been extensively studied in the past. In particular, a role of matrix metalloproteinase 3 (MMP3) in the disease initiation and progression has been recently reported. However, an involvement of Insulin-like growth factor 1 (IGF-I)-stimulated phosphatidylinositol-3 kinase (PI3k) / Akt signaling pathway-mediated control of MMP3 in LDD has not been acknowledged. Methods: We examined the serum IGF-1 levels and activation of the receptor for IGF-1 (IGF-1R) in resected discs in patients with LDD, compared to the fractured discs from traumatized, non-LDD subjects as a control. We analyzed the effects of IGF-1 on the activation of IGF-1R, Akt and MMP3 in a human nucleus pulposus SV40 cell line (HNPSV). We transfected HNPSV cells with a constitutive nuclear FoxO1, and analyzed its effect on the activation of IGF-1R, Akt and MMP3. Results: LDD patients had significantly lower levels of serum IGF-1, and LDD discs had significantly lower levels of activated IGF-1R. IGF-1 induced phosphorylation of IGF-1R, and then phosphorylation of its downstream factor Akt in the HNPSV cells, resulting in significantly inhibition of MMP3. Further, FoxO1 nuclear retention completely abolished the inhibitory effects of IGF-1 on MMP3 in HNPSV cells. Conclusion: Together, IGF-1/Akt/FoxO1/MMP3 regulatory machinery may control the development of LDD.