摘要环境污染的日益加剧与日益提高的环境标准都要求我们在环境问题的处理上能有所 突破。CO2 在碳氢燃料生产中的循环利用为可持续清洁能源的发展提供了另一种可能性。 在过去的十年里,已经进行了许多的研究用来解决捕获 CO2 和 H2O 并将其转化为太阳能 燃料的问题。例如,金华业等人研究了用于光催化反应的具有有序中孔结构的掺杂半导体, 以开辟开发用于选择性催化 CO2 还原的可见光活性光催化剂的新的战略方法。一般来说, 以无机半导体为催化剂的 CO2 光还原反应或多或少是模拟自然光合的过程。然而,人工 光合作用的效率通常比天然光低得多,这主要是由于需要同时满足苛刻的氧化还原反应条 件和质子和电子的同步充足。一种有效的方式是源自太阳能驱动的 CO2 和 H2O 的热化学 转换,由于使用整个太阳光谱(特别是通过红外光),被证明是最有效的太阳能燃料。这 种方式是基于金属氧化物的氧化还原反应依赖于氧的摄取和氧化还原物质的释放能力。然 而,在大多数公开的研究中,CO2 和 H2O 的分裂作为燃料被用来获得 CO 和 H2。但是仍 然需要对具有独特选择性和高效率的热反应的烃燃料的进一步研究。这些挑战为寻找具有 高吸收和释放能力的选择性催化剂提供了主要动力,即在晶格内产生较高浓度的氧空位。 而利用四氧化三钴的纳米粉体作为催化剂光热催化还原 CO2 在近几年的研究中受到了广 泛的关注。本课题就是通过溶剂热法,将硝酸钴、无水乙醇和三乙胺在加热条件下剧烈反 应制成具有正常的 AB2O4 尖晶石构造的纳米四氧化三钴。并且通过在纳米四氧化三钴中 掺杂不同浓度的 Mn(NO3)2、Ni(NO3)2、Fe(NO3)2、Zn(NO3)2 研究在不同浓度下的纳米四氧 化三钴的催化效率。最后通过 X 射线衍射(XRD)、扫描(透射)电镜(TEM)、差热 分析(TG)、比表面积(BET)、光催化还原测试等步骤研究掺杂了分别掺杂了 5%、10%、 15%、25%、50%和 75%浓度的 Zn、Mn、Ni、Fe 元素制备的尖晶石结构的纳米 Co3O4 的 光热催化性能。66298
毕业论文关键词:纳米 Co3O4;催化还原 CO2;不同元素掺杂
Study on the preparation and catalytic properties of nano cobalt three four oxidation solvent thermal method
Abstract
To an increasing extent, environmental pollution and standards seriously require us to make breakthroughs in the treatment of environmental problems.he recycling of CO2 in hydrocarbon fuel production provides another possibility for the development of sustainable clean energy. Over the past decade, a number of studies have been conducted to address the problem of capturing CO2 and converting H2O into solar fuels. However, the efficiency of artificial photosynthesis is usually much lower than that of natural light, mainly due to the need to meet both the harsh redox reaction conditions and the sufficient synchronization of protons and electrons. An effective way is derived from solar-driven CO2 and H2O thermochemical conversion due to the use of the entire solar spectrum (especially by infrared light), which has proven to be the most effective solar fuel. This method is based on the redox reaction of the metal oxide depending on the oxygen uptake and the ability of the redox release. However, in most public studies, the partition of CO2 and H2O was used as fuel to obtain CO and H2O. There is still a need for further study of hydrocarbon fuels with a unique selectivity and high efficiency of the thermal reaction. These challenges provide the primary impetus for finding selective catalysts with high absorption and release capabilities, ie generating higher concentrations of oxygen vacancies in the lattice. The photocatalytic reduction of CO2 by using carbon monoxide tetroxide as a catalyst has been paid more and more attention in recent years. This graduation design is through the hot solvent method, the cobalt nitrate, ethanol and