Highly efficient catalysts with enough selectivity and stability are essential for electrochemical nitrogen reduction reaction (e-NRR) that has been considered as a green and sustainable route for synthesis of NH 3 . In this work, a series of three-dimensional (3D) porous iron foam (abbreviated as IF) selfsupported FeS 2 −MoS 2 bimetallic hybrid materials, denoted as FeS 2 −MoS 2 @IF x , x = 100, 200, 300, and 400, were designed and synthesized and then directly used as the electrode for the NRR. Interestingly, the IF serving as a slow-releasing iron source together with polyoxomolybdates (NH 4 ) 6 Mo 7 O 24 •4H 2 O as a Mo source were sulfurized in the presence of thiourea to form self-supported FeS 2 −MoS 2 on IF (abbreviated as FeS 2 −MoS 2 @IF 200 ) as an efficient electrocatalyst. Further material characterizations of FeS 2 −MoS 2 @IF 200 show that flower cluster-like FeS 2 −MoS 2 grows on the 3D skeleton of IF, consisting of interconnected and staggered nanosheets with mesoporous structures. The unique 3D porous structure of FeS 2 −MoS 2 @IF together with synergy and interface interactions of bimetallic sulfides would make FeS 2 −MoS 2 @IF possess favorable electron transfer tunnels and expose abundant intrinsic active sites in the e-NRR. It is confirmed that synthesized FeS 2 −MoS 2 @IF 200 shows a remarkable NH 3 production rate of 7.1 ×10 −10 mol s −1 cm −2 at −0.5 V versus the reversible hydrogen electrode (vs RHE) and an optimal faradaic efficiency of 4.6% at −0.3 V (vs RHE) with outstanding electrochemical and structural stability.

Precise design and construction of catalysts with satisfied performance for ambient electrolytic nitrogen reduction reaction (e-NRR) is extremely challenging. By in situ integrating an electron-rich polyoxometalates (POMs) into stable metal organic frameworks (MOFs), five POMs-based MOFs formulated as [Fe x Co y (Pbpy) 9 (ox) 6 (H 2 O) 6 ][P 2 W 18 O 62 ]•3H 2 O (abbreviated as Fe x Co y MOF-P 2 W 18 ) are created and directly used as catalysts for e-NRR. Their electrocatalytic performances are remarkably improved thanks to complementary advantages and promising possibilities of MOFs and POMs. In particular, NH 3 yield rates of 47.04 µg h −1 mg cat. −1 and Faradaic efficiency of 31.56% by FeCoMOF-P 2 W 18 for e-NRR are significantly enhanced by a factor of 4 and 3, respectively, compared to the [Fe 0.5 Co 0.5 (Pbpy)(ox)] 2 •(Pbpy) 0.5 . The cyclic voltammetry curves, density functional theory calculations and in situ Fouriertransform infrared spectroscopy confirm that there is a directional electron channel from P 2 W 18 to the MOFs unit to accelerate the transfer of electrons. And the introduction of bimetals Fe and Co in the P 2 W 18 -based MOFs can reduce the energy of the *N 2 to *N 2 H step, thereby increasing the production of NH 3 . More importantly, this POM in situ embedding strategy can be extended to create other e-NRR catalysts with enhanced performances, which opens a new avenue for future NH 3 production for breakthrough in the bottleneck of e-NRR.

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Heart is one of the most significant organs in mammalian animals, it functions as a pump to make the blood flow from heart to the body tissue and turn back to heart, which can provide the oxygen and other nutrients with the body tissue and carry the waste from the body 86tissue. There is an increase found in the incidence of heart disease and the case fatality rate of heart disease all over the world, this is because the heart disease leads to the greater amounts of cardiomyocyte dead and the capability of cardiomyocyte proliferation is weaker. To treat the heart disease and recover the capability of cardiomyocyte proliferation, this article summaries three factors that can affect the capability of cardiomyocyte proliferation, which may help with the treatment of heart disease in the future.