Novak Travis G, Prakash Om, Tiwari Anand P, Jeon Seokwoo
Department of Materials Science and Engineering, KAIST Institute for the Nanocentury, Advanced Battery Center, KAIST Daejeon 305-701 Republic of Korea
Department of Inorganic and Physical Chemistry, Indian Institute of Sciences Bengaluru 560012 India.
RSC Adv. 2019 Jan 2;9(1):234-239. doi: 10.1039/c8ra09261c. eCollection 2018 Dec 19.
Transition metal phosphides are among the most promising materials for achieving efficient electrocatalytic performance without the use of rare or expensive noble metals. However, previous research into phosphides for the hydrogen evolution reaction (HER) or oxygen evolution reaction (OER) has focused on high-temperature vapor-phase processes, which are not practical for large-scale applications. Here, we introduce a simple, one-step solution-phase method of phosphide synthesis by modifying CuWS using triphenylphosphine (TPP), which serves to substitute S with P and transform the normally inactive basal plane of CuWS into a defect-rich, activated basal plane. The OER activity was significantly enhanced by phosphorus substitution, with the resulting Tafel slope of the sample with ∼8 at% phosphorus reaching 194 mV dec, a result close to that of the best OER catalyst (RuO, 151 mV dec). The sample possessed stable OER performance, showing no degradation in current density over ∼24 hours (500 cycles), proving the robust and stable nature of the phosphorus substitution. These results open the possibility for further phosphide catalyst development using this low-cost, solution-phase method.
过渡金属磷化物是在不使用稀有或昂贵贵金属的情况下实现高效电催化性能的最有前途的材料之一。然而，先前对用于析氢反应（HER）或析氧反应（OER）的磷化物的研究集中在高温气相过程上，这对于大规模应用来说并不实用。在这里，我们介绍一种简单的一步溶液相磷化物合成方法，即使用三苯基膦（TPP）修饰CuWS，这有助于用P替代S，并将通常无活性的CuWS基面转变为富含缺陷的活化基面。通过磷取代，OER活性显著增强，磷含量约为8 at%的样品的塔菲尔斜率达到194 mV dec，这一结果接近最佳OER催化剂（RuO，151 mV dec）的结果。该样品具有稳定的OER性能，在约24小时（500次循环）内电流密度没有下降，证明了磷取代的稳健性和稳定性。这些结果为使用这种低成本的溶液相方法进一步开发磷化物催化剂开辟了可能性。
