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Synthesis and magnetic properties of nanocrystals (size ≃22 nm) of cubic spinel MgMnO3 with the defect structure [Mg2+][Mg1/32+Mn4/34+□1/3]O4 are reported. Analysis of the magnetization M versus T (2–370 K) and M versus H (up to 65 kOe) data shows a blocking temperature TB≃11 K and an estimated Néel temperature TN∼150 K above which the Weiss temperature θ=-7 K and μ=3.91 μB/Mn4+. For TB

Synthesis and magnetic properties of nanocrystals (size ≃22 nm) of cubic spinel MgMnO3 with the defect structure [Mg2+][Mg1/32+Mn4/34+□1/3]O4 are reported. Analysis of the magnetization M versus T (2–370 K) and M versus H (up to 65 kOe) data shows a blocking temperature TB≃11 K and an estimated Néel temperature TN∼150 K above which the Weiss temperature θ=-7 K and μ=3.91 μB/Mn4+. For TBN, fit of the M versus H data to modified Langevin function yields 35 μB as magnetic moment/particle, resulting from the defect structure. [ABSTRACT FROM AUTHOR]

The authors report on carbon-assisted water electrolysis at 300 K which only consumes 9.6 kcal/mol H2O (compared to 56.7 kcal/mol H2O for ordinary electrolysis) using the net reaction C(s)+2H2O(ℓ)→CO2(g)+2H2(g). Carbon-assisted H2 production and its kinetics/energetics are measured at applied potential |E0| between 0.1 and 1.8 V (compared to |E0| >1.25 V required for water electrolysis). Surprisingly, H2 produced per W h is higher at the lower voltages, but longer times are required to produce the same amount of H2 The suggested practical conditions are |E0|≃0.5 V and carbon concentration of 0.08 g/cm3. [ABSTRACT FROM AUTHOR]

A correction to the article "Carbon-assisted water electrolysis: An energy-efficient process to produce pure H2 at room temperature," published in the previous issue is presented.