超薄MOF纳米片为前驱体制备三维网络状碳基杂化材料及其电催化析氢性能研究

As one of the biggest challenges in production and utilization of hydrogen energy, the development of a highly active, stable and low-cost non-noble-metal electrocatalyst for electrocatalytic hydrogen evolution reaction is of great importance. In this proposal, a novel electrocatalyst constructed by carbon-based hybrids is to be developed. Relying on the building blocks of the ultrathin MOF nanosheets with unique 2D morphology and the doped 3D graphene networks, the novel MOF/graphene hybrids are prepared by in situ synthesis method or electrophoretic deposition, in which a face-to-face stacking structure and strong interfacial interaction are formed between MOF nanosheets and graphene. Then, the MOF/graphene hybrids are subjected to an annealing process followed by an acid treatment to obtain the carbon-based nanohybrids with 3D network-like structure. The performance of the prepared carbon-based nanohybrids as electrocatalysts for hydrogen evolution reaction is to be evaluated under different pH conditions. A systematic investigation is also to be conducted on the formation mechanism of the MOF/graphene hybrids, the interfacial forces between MOF nanosheets and graphene, the synergistic effects between the carbonized MOFs and 3D graphene networks, as well as effects of various factors on the performance of the prepared carbon-based nanohybrids. With this project, a novel, economic and scalable synthetic method is expected to establish for non-noble-metal electrocatalysts used for electrocatalytic hydrogen generation, which will be beneficial for the practical application of carbon-based materials in hydrogen generation.

如何开发一种活性高、稳定性好和价格低廉的非贵金属催化剂用于电催化水解析氢反应对高效制氢及有效利用氢气能源至关重要，迄今尚未解决。本研究拟开发一种由碳基杂化材料构成的新型电催化剂结构，将采用具有二维超薄纳米片结构的MOF晶体和具有三维网络结构的掺杂石墨烯为构建单元，基于原位合成或电泳沉积的方法制备“面对面”紧密堆叠结构的MOF/石墨烯杂化材料。进一步利用煅烧和酸处理工艺，将上述产物转化成三维网络状的碳基纳米杂化材料，并研究其在不同酸碱环境下的电催化析氢性能。深入研究体系内MOF/石墨烯杂化材料的合成机理，MOF纳米片与石墨烯的界面作用关系，MOF煅烧产物与掺杂三维石墨烯的协同作用规律，以及各因素对碳基杂化材料电催化析氢性能的影响规律。本项目可望为电催化水解析氢反应提供一种新型的、廉价的和可量产的非贵金属催化剂及其制备方法，相关成果有助于推进碳基材料在制氢领域中的规模化应用。

复合电极材料的微观结构对其电化学活性至关重要，如何充分发挥各组分的协同作用以提升整体活性是急需解决的问题。本项目发展了利用MOF与石墨烯的可控组装结构以提升材料电化学活性的新思路，开发了MOF-石墨烯复合材料及其衍生电极材料的多种制备及调控手段，摸清了电化学反应中MOF及其衍生物与石墨烯的协同作用机制，提出了基于二维材料组装结构的一体化自支撑电极的设计策略，为催化、能源等领域所需的MOF-石墨烯复合材料提供了多种有效、低成本、易操作的制备途径，为电化学应用及柔性器件所需的兼具机械强度和电化学稳定性的电极材料的开发提供了新思路。主要研究成果如下。.（1）开发了三维宏观体结构MOF-石墨烯复合材料及其衍生电极材料的制备方法，具有简单、快速、普适性和产物组分比例可调的特点。.（2）发展了调控MOF-石墨烯复合材料及其衍生材料的密度、导电性、电化学活性面积和宏观结构的有效手段。相比文献常用冷冻干燥法制备的复合材料，我们的调控手段可提升材料密度高达130倍、导电性达3个数量级，并赋予其高结构稳定性和柔韧性。.（3）开发了基于MOF衍生多级结构的电催化剂材料的可控制备策略，实现了基于二维过渡金属化合物纳米片的多级组装结构的简单、廉价、量化和普适制备。所制得的样品在电催化析氧反应中展现了优于大多已报道类似催化剂材料的性能，且具有高稳定性，在可充电锌空电池中有应用前景。.（4）发展了基于二维MOF衍生材料的“多层次”一体化多功能电催化电极的设计思路。制得的基于阵列结构非3d金属掺杂异质结纳米片的电极材料在电催化析氢、析氧反应中展现了优于商品化催化剂和其他近期相关报道的双功能催化剂的性能。此外，其自支撑、无粘合剂的电极结构适用于便携式的水分解器件，为产氢提供了一种低成本的方法，为高活性非贵金属电催化材料的开发提供了一种思路。. 项目共发表SCI收录学术论文13篇（含Chem. Soc. Rev. 1篇，Adv. Sci.1篇，Chem. Mater. 1篇，Small 1篇，J. Mater. Chem. A.2篇），其中ESI高被引论文1篇。