苏州大学苏韧研究团队报道了芳香族羰基光催化加氢还原条件下氧化钯表面的形成与稳定。相关研究成果发表在2023年2月28日出版的《美国化学会杂志》。

光催化为芳香族羰基化合物氢化为无氧芳香族化合物提供了一种环保的途径，这是化学工业中的一种重要精制工艺，通常在高温高压氢气下进行。然而，芳香族羰基通常仅部分氢化为醇，醇容易脱附，在环境条件下很难进一步脱氧。

该文中，通过在负载在石墨碳氮化物上的Pd助催化剂上构建氧化物表面，通过逐步缩醛化和氢化，芳香族羰基化合物的另一种氢化途径变得可用，从而能够高效和选择性地生产不含O的芳香族化合物。PdO表面实现反应物和中间体的最佳吸附以及从醇供体中快速提取氢，有利于羰基的快速缩醛化及其连续氢化为无氧烃。在410nm照射下，苯甲醛光催化加氢生成甲苯的选择性大于90%，量子效率为～10.2%。通过向反应溶液中添加微量HCl，PdO表面在高浓度下长期运行时保持稳定和活性，为实际应用提供了前景。

附：英文原文

Title: Creating and Stabilizing an Oxidized Pd Surface under Reductive Conditions for Photocatalytic Hydrogenation of Aromatic Carbonyls

Author: Wei Qiao, Xing Fan, Weifeng Liu, Fahir Niaz Khan, Dongsheng Zhang, Feiyu Han, Huiyu Yue, Yajiao Li, Nikolaos Dimitratos, Stefania Albonetti, Xiaodong Wen, Yong Yang, Flemming Besenbacher, Yongwang Li, Hans Niemantsverdriet, Haiping Lin, Ren Su

Issue&Volume: February 28, 2023

Abstract: Photocatalysis provides an eco-friendly route for the hydrogenation of aromatic carbonyls to O-free aromatics, which is an important refining process in the chemical industry that is generally carried out under high pressure of hydrogen at elevated temperatures. However, aromatic carbonyls are often only partially hydrogenated to alcohols, which readily desorbs and are hardly further deoxygenated under ambient conditions. Here, we show that by constructing an oxide surface over the Pd cocatalyst supported on graphitic carbon nitride, an alternative hydrogenation path of aromatic carbonyls becomes available via a step-wise acetalization and hydrogenation, thus allowing efficient and selective production of O-free aromatics. The PdO surface allows for optimum adsorption of reactants and intermediates and rapid abstraction of hydrogen from the alcohol donor, favoring fast acetalization of the carbonyls and their consecutive hydrogenation to O-free hydrocarbons. The photocatalytic hydrogenation of benzaldehyde into toluene shows a high selectivity of >90% and a quantum efficiency of ～10.2% under 410 nm irradiation. By adding trace amounts of HCl to the reaction solution, the PdO surface remains stable and active for long-term operation at high concentrations, offering perspective for practical applications.

DOI: 10.1021/jacs.2c13196

Source: https://pubs.acs.org/doi/10.1021/jacs.2c13196