硼氢化钠醇解可控制氢催化剂的制备及构效关系研究

The current energy system based on fossil-fuels has been identified as the major cause of global climate change and local air pollution. Fuel cells which use H2 for power have significant environmental advantages。Sodium borohydride (NaBH4) has been extensively investigated as a potential hydrogen storage material. Hydrolysis and alcoholysis of sodium borohydride is the most effective way to release the hydrogen in sodium borohydride. The Hydrolysis of sodium borohydride has been studied by many researcher, But studies of sodium borohydride alcoholysis just started. So,The development of catalyst materials for on demand NaBH4 alcoholysis is key research areas. The design, simulation, emulation and analysis of catalyst for hydrogen production from NaBH4 alcoholysis were carried out by computer.According to the optimization design, the catalyst is deposited firmly over the block shape carrier surface by electroless and electro plating to improve the hydrogen and caustic embrittlement resistance of the catalyst and extend the life of the catalyst. The catalyst and reaction solution can be effective separated using block shape catalyst, the hydrogen generation can be controlled.Study the structure activity relationship between microscopic structure, surface chemical species and macroscopic performance of the catalyst and reaction kinetics of sodium borohydride catalytic alcoholysis by means of modern instruments analysis method, computation module, emulation and hydrogen production performance of catalyst. Theoretical support and experimental instructions could be provided to prepare catalyst for Controllable generation of hydrogen from NaBH4 catalyst.

氢气作为原料产生动力的燃料电池是环境友好型能量供应系统，能够避免化石能量系统产生的环境污染。硼氢化钠是潜力巨大的氢气存储材料，硼氢化钠水解和醇解是释放硼氢化钠中氢最有效的方法，目前硼氢化钠水解的研究已经相当多和比较成熟，但是硼氢化钠醇解的研究刚刚起步。因此开发硼氢化钠醇解制氢催化剂是目前最重要的研究方向之一。本项目运用计算机对硼氢化钠催化醇解制氢催化剂进行设计、模拟、仿真和分析，得到最优化结果。根据最优化结果采用在化学镀的基础上，通过电镀将催化剂牢固负载于块状载体之上，提高催化剂抗氢脆和碱脆能力，增强催化剂的寿命，块体催化剂可以有效实现固液分离，达到可控制氢的目标。运用现代仪器表征方法和测试手段，结合计算、模拟和仿真以及催化剂制氢性能，探索制氢催化剂的微观结构、表面状态与宏观性能之间的构效关系，探明硼氢化钠催化醇解的反应动力学问题，为硼氢化钠制氢催化剂的研究提供规律性研究结果和理论依据。

运用计算化学模拟软件和采用材料基因组学思想，利用分子模拟和调控技术构建表面结构稳定、高催化活性的硼氢化钠醇解制氢催化剂模型。通过增加载体的比表面积和金属合金化来提高硼氢化钠醇解制氢催化剂的催化活性。运用现代仪器分析表征手段和测试方法对所合成催化剂进行结构及性能测试。取得的研究成果有：. 以Ni基和Pt基为例，从电子结构和原子层次揭示了硼氢化钠制氢合金催化剂的结构、热稳定性、扩散性能、表面吸附及氧化还原反应机理。通过调控金属纳米催化剂的组成、尺寸、形貌、原子排列等，设计出了高活性高稳定性的催化剂，并通过建立相图模型和构效关系形成一套完整的该类材料设计框架。. 利用化学还原法制备制备了Ru-Co/C、Ru-Co/CNTs、Ru-Fe/GO高活性粉末型合金催化剂，重点考察了金属配比和反应物浓度对催化剂活性的影响，优化催化剂的制备工艺。其中Ru-Co/CNTs催化剂催化硼氢化钠甲醇醇解制氢的最高速率可达到21.19 L·min-1·g-1，活化能仅为34.35 kJ·mol-1。. 采用化学镀、电镀方法制备了Co-P/Ni foam、Co-P/CNTs/Ni foam、Ru/Ni foam、Co-Mo-P/CNTs-Ni foam、Ru-Ni/Ni foam、Ru/NiO-Ni foam 块状催化剂，实现了真正的可控制氢，并通过增加了块状载体Ni foam的比表面积，使金属在载体上均匀的三维生长，增加了催化剂的活性位点，进而增强催化剂的催化活性。其中，新型的Co-P/CNTs/Ni foam复合材料合金催化剂在最佳制备条件下制备出的催化剂的最大制氢速率可达2.3 L·min-1·g-1，催化硼氢化钠甲醇解反应的表观活化能为47.74 kJ·mol-1，低于硼氢化钠自醇解的活化能52.96 kJ·mol-1。. 发表相关研究论文14篇，申请发明专利4项，培养研究生8名。. 通过本项目的研究，在硼氢化钠醇解可控制氢催化剂的结构设计、批量制备、微观形貌表征、催化性能评价做了系统的研究，为高催化活性和稳定性的硼氢化钠醇解可控制氢催化剂的制备提供了一定的理论依据和实践基础。相关研究结果有力的推动了硼氢化钠制氢的理论研究及产业化应用。