کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7935286 1513052 2018 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Hydrogen production under visible illumination on the spinel NiMn2O4 prepared by sol gel
موضوعات مرتبط
مهندسی و علوم پایه مهندسی انرژی انرژی های تجدید پذیر، توسعه پایدار و محیط زیست
پیش نمایش صفحه اول مقاله
Hydrogen production under visible illumination on the spinel NiMn2O4 prepared by sol gel
چکیده انگلیسی
The spinel NiMn2O4 prepared by sol-gel is applied for the hydrogen liberation upon visible light. The oxide crystallizes in a cubic symmetry with a crystallite dimension of 63 nm, smaller than that obtained by transmission electron microscopy (TEM; 470 nm), indicating crystallites agglomeration. p-type conductivity is demonstrated by the positive thermo power (+130 µV at 300 K), with a hole mobility of 2.09 × 10−4 cm2 V−1 s−1 and an activation energies of 70 meV. The optical gap (1.13 eV), attributed to 3d orbital splitting, is determined from the diffuse reflectance and is appropriately matched to the sun spectrum. The physical and chemical characterizations are correlated to show the feasibility of NiMn2O4 for the hydrogen formation. The capacitance measurement gives a flat band potential of −0.20 VSCE and a hole density of 0.29 × 1016 cm−3. The potential of the conduction band (−1.26 VSCE) is below that of H2O/H2 level (∼−0.40 VSCE), allowing H2-liberation upon visible irradiation. The NiMn2O4 mass, pH and concentration of the hole scavenger S2O32− are optimized. Under optimized conditions, the H2volume liberation reaches 77 µmol with rate of 0.024 µmol mg−1 min−1.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solar Energy - Volume 166, 15 May 2018, Pages 220-225
نویسندگان
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