Yao Zhiwei, Li Meng, Wang Xiang, Qiao Xue, Zhu Jiang, Zhao Yu, Wang Guanzhang, Yin Jingzhou, Wang Haiyan
College of Chemistry, Chemical Engineering and Environmental Engineering, Liaoning Shihua University, Liaoning, PR China 113001.
Dalton Trans. 2015 Mar 28;44(12):5503-9. doi: 10.1039/c4dt03886j.
A novel synthetic route was developed to prepare nano-sized and well-dispersed phosphides of transition metals (Mo, Ni, and Co) from their corresponding oxide precursors. The current approach produced metal phosphides in dimethyl ether (DME) using the rapid heating reduction (RHR) method. The synthesis of phosphides in DME was interesting, since the composition of gas-phase products was predominantly H2, CO and CH4 with a minor amount of CO2 but without H2O. Based on XRD and MS results, the formation mechanism of the phosphides was proposed. The overall synthesis process cannot simply be regarded as the reduction of an oxide precursor and the decomposition of DME. The product distribution should be ascribed to a combination of other catalytic reactions. In addition, it is noteworthy that compared with the traditional method, viz. temperature-programmed reduction in H2 (TPR-H2), the present method used a higher heating rate to shorten the reaction time and can yield more finely dispersed metal phosphide nanoparticles. The good dispersion of phosphide nanoparticles is probably achieved due to the fact that no H2O was released in the RHR-DME process, which can avoid strong hydrothermal sintering.
开发了一种新的合成路线，用于从相应的氧化物前驱体制备纳米级且分散良好的过渡金属（钼、镍和钴）磷化物。目前的方法是使用快速加热还原（RHR）法在二甲醚（DME）中制备金属磷化物。在DME中合成磷化物很有趣，因为气相产物的组成主要是H2、CO和CH4，少量CO2，但没有H2O。基于XRD和MS结果，提出了磷化物的形成机理。整个合成过程不能简单地看作是氧化物前驱体的还原和DME的分解。产物分布应归因于其他催化反应的组合。此外，值得注意的是，与传统方法（即H2程序升温还原（TPR-H2））相比，本方法使用了更高的加热速率来缩短反应时间，并且可以产生更细分散的金属磷化物纳米颗粒。磷化物纳米颗粒的良好分散可能是由于在RHR-DME过程中没有释放H2O，这可以避免强烈的水热烧结。
