采用KOH溶液在通电条件下对Fe_3N纳米颗粒表面改性的方法,探究了碱化处理对Fe_3N纳米颗粒电催化性能的影响。采用XRD、TEM、EDX、XPS、拉曼光谱和傅立叶变换红外光谱对碱化前后的Fe_3N样品进行形貌和成分的表征,采用时间电流曲线、LSV...采用KOH溶液在通电条件下对Fe_3N纳米颗粒表面改性的方法,探究了碱化处理对Fe_3N纳米颗粒电催化性能的影响。采用XRD、TEM、EDX、XPS、拉曼光谱和傅立叶变换红外光谱对碱化前后的Fe_3N样品进行形貌和成分的表征,采用时间电流曲线、LSV曲线、Tafel斜率、交流阻抗法和CV曲线对碱化前后的Fe_3N样品进行电催化制氢(HER)性能的分析。结果表明,用KOH处理的Fe_3N样品,平均晶粒尺寸由(80±10)nm缩小为(70±10)nm,形状由破碎的链状结构变为椭圆形结构,物相由e-Fe_3N相部分转变为α-Fe2O3相;尺寸、形貌和成分的改变,使得碱化后的样品有更多的电催化活性位点暴露。由电流密度为10 m A/cm2的过电位0.429 V降为0.204 V,Tafel斜率由103 m V/dec降为95 m V/dec。过电势降低,交流阻抗变小,电化学活性面积增大,表明KOH碱化处理后的样品电催化制氢的能力得到大大提高。展开更多
Wheat straw biodegradability during anaerobic digestion was improved by treatment with potassium hydroxide （KOH） to decrease digestion time and enhance biomethane production and fertility value. KOH concentrations o...Wheat straw biodegradability during anaerobic digestion was improved by treatment with potassium hydroxide （KOH） to decrease digestion time and enhance biomethane production and fertility value. KOH concentrations of 1% （KI）, 3% （[（2）, 6% （K3） and 9% （l（4） were tested for wheat straw pretreatment at ambient temperature with a C：N ratio of 25：1.86% of total solids （TS）, 89% of volatile solids （VS） and 22% of lignocellulose, cellulose and hemi- cellulose （LCH） （22%） were decomposed effectively with the wheat straw pretreated by 6% KOH. Enhanced bio- gas production and cumulative biomethane yield of 258 ml. （g VS）-1 were obtained increased by 45% and 41% respectively, compared with untreated wheat straw. Pretreated wheat straw digestion also yielded a digestate with higher fertilizer values potassium （l 38%）, calcium （22%） and magnesium （16%）. These results show that TS, VS and LCH can be effectively removed from wheat straw pretreated with KOH, improving biodegradability biomethane production and fertilizer value.展开更多
文摘采用KOH溶液在通电条件下对Fe_3N纳米颗粒表面改性的方法,探究了碱化处理对Fe_3N纳米颗粒电催化性能的影响。采用XRD、TEM、EDX、XPS、拉曼光谱和傅立叶变换红外光谱对碱化前后的Fe_3N样品进行形貌和成分的表征,采用时间电流曲线、LSV曲线、Tafel斜率、交流阻抗法和CV曲线对碱化前后的Fe_3N样品进行电催化制氢(HER)性能的分析。结果表明,用KOH处理的Fe_3N样品,平均晶粒尺寸由(80±10)nm缩小为(70±10)nm,形状由破碎的链状结构变为椭圆形结构,物相由e-Fe_3N相部分转变为α-Fe2O3相;尺寸、形貌和成分的改变,使得碱化后的样品有更多的电催化活性位点暴露。由电流密度为10 m A/cm2的过电位0.429 V降为0.204 V,Tafel斜率由103 m V/dec降为95 m V/dec。过电势降低,交流阻抗变小,电化学活性面积增大,表明KOH碱化处理后的样品电催化制氢的能力得到大大提高。
基金Supported by Specialized Research Fund for the Doctoral Program of Higer Education(20120010110004)the Natural Science Foundation of Beijing(8142030)
文摘Wheat straw biodegradability during anaerobic digestion was improved by treatment with potassium hydroxide （KOH） to decrease digestion time and enhance biomethane production and fertility value. KOH concentrations of 1% （KI）, 3% （[（2）, 6% （K3） and 9% （l（4） were tested for wheat straw pretreatment at ambient temperature with a C：N ratio of 25：1.86% of total solids （TS）, 89% of volatile solids （VS） and 22% of lignocellulose, cellulose and hemi- cellulose （LCH） （22%） were decomposed effectively with the wheat straw pretreated by 6% KOH. Enhanced bio- gas production and cumulative biomethane yield of 258 ml. （g VS）-1 were obtained increased by 45% and 41% respectively, compared with untreated wheat straw. Pretreated wheat straw digestion also yielded a digestate with higher fertilizer values potassium （l 38%）, calcium （22%） and magnesium （16%）. These results show that TS, VS and LCH can be effectively removed from wheat straw pretreated with KOH, improving biodegradability biomethane production and fertilizer value.
