【摘要】 设计钛基金属有机骨架（MOF）实现高效光催化CO₂还原具有重要意义但仍极具挑战.本文发展了一种新的一步原位水蚀刻方法制备超细Pd纳米颗粒/多级孔Ti-MOFs高效光催化剂,其中水刻蚀在形成多级孔结构的同时也为Pd的锚定提供了丰富位点,进而在光还原的作用下一步实现Pd纳米颗粒在MOFs表面和内部的负载.得益于多级孔结构和超细Pd颗粒负载,Pd/hMUV-10在350℃光照下的CO产率高达65.9 mmol g^-1 h^-1,比目前最先进的MOF基催化剂高出约两个数量级,并超过大多数已报道的无机半导体基催化剂.在200℃相对温和的条件下,CO的产率也达到3.36 mmol g^-1 h^-1.在350℃的连续循环测试中,催化剂活性几乎没有衰减.理论计算表明,Pd负载可增强对CO₂的吸附和降低CO₂还原能垒,从而实现高效光热CO₂还原.本文所报道的Pd/hMUV-10催化剂有望在工业CO₂捕获和转化中得到应用.更多还原

【Abstract】 The exploration of robust titanium-based metalorganic framework（MOF） photocatalysts for efficient CO₂reduction is of critical significance but remains challenging.Herein,a hierarchically porous titanium-MOF（hMUV-10）anchored with ultrafine Pd nanoparticles was rationally designed via a convenient one-step in-situ water-etching strategy.The hierarchical MUV-10 structure provided abundant sites for the anchoring of Pd nanoparticles on the outside and inside of MOFs.The optimized Pd/hMUV-10 demonstrated an ultrahigh CO production rate of 65.9 mmol g^-1 h^-1 under light irradiation at 350℃,approximately two orders of magnitude higher than the state-of-the-art MOF-based catalysts and surpassed most reported inorganic semiconductor-based catalysts.The CO production rate under a relatively mild temperature of 200℃ also reached as high as3.36 mmol g^-1 h^-1,and negligible activity decay was observed during continuous cycling measurement under 350℃.Theoretical calculations suggested that Pd enhanced CO₂ adsorption ability and reduced the energy barrier for CO₂ reduction,thereby leading to a highly improved CO yield from photothermal CO₂ reduction.更多还原