Yang Jing, Guo Donghua, Zhao Shulin, Lin Yue, Yang Rui, Xu Dongdong, Shi Naien, Zhang Xiaoshu, Lu Lingzhi, Lan Ya-Qian, Bao Jianchun, Han Min
Jiangsu Key Laboratory of Biofunctional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, P. R. China.
Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, P. R. China.
Small. 2019 Mar;15(10):e1804546. doi: 10.1002/smll.201804546. Epub 2019 Jan 28.
As one class of important functional materials, transition metal phosphides (TMPs) nanostructures show promising applications in catalysis and energy storage fields. Although great progress has been achieved, phase-controlled synthesis of cobalt phosphides nanocrystals or related nanohybrids remains a challenge, and their use in overall water splitting (OWS) is not systematically studied. Herein, three kinds of cobalt phosphides nanocrystals encapsulated by P-doped carbon (PC) and married with P-doped graphene (PG) nanohybrids, including CoP@PC/PG, CoP-Co P@PC/PG, and Co P@PC/PG, are obtained through controllable thermal conversion of presynthesized supramolecular gels that contain cobalt salt, phytic acid, and graphene oxides at proper temperature under Ar/H atmosphere. Among them, the mixed-phase CoP-Co P@PC/PG nanohybrids manifest high electrocatalytic activity toward both hydrogen and oxygen evolution in alkaline media. Remarkably, using them as bifunctional catalysts, the fabricated CoP-Co P@PC/PG||CoP-Co P@PC/PG electrolyzer only needs a cell voltage of 1.567 V for driving OWS to reach the current density at 10 mA cm , superior to their pure-phase counterparts and recently reported bifunctional catalysts based devices. Also, such a CoP-Co P@PC/PG||CoP-Co P@PC/PG device exhibits outstanding stability for OWS. This work may shed some light on optimizing TMPs nanostructures based on phase engineering, and promote their applications in OWS or other renewable energy options.
作为一类重要的功能材料，过渡金属磷化物（TMPs）纳米结构在催化和储能领域展现出了广阔的应用前景。尽管已经取得了很大进展，但磷化钴纳米晶体或相关纳米杂化物的相控合成仍然是一个挑战，并且它们在全水解（OWS）中的应用尚未得到系统研究。在此，通过在Ar/H气氛下，在适当温度下对预先合成的包含钴盐、植酸和氧化石墨烯的超分子凝胶进行可控热转化，获得了三种由P掺杂碳（PC）包裹并与P掺杂石墨烯（PG）纳米杂化物结合的磷化钴纳米晶体，包括CoP@PC/PG、CoP-Co P@PC/PG和Co P@PC/PG。其中，混合相CoP-Co P@PC/PG纳米杂化物在碱性介质中对析氢和析氧均表现出高电催化活性。值得注意的是，使用它们作为双功能催化剂，制备的CoP-Co P@PC/PG||CoP-Co P@PC/PG电解槽在驱动OWS达到10 mA cm的电流密度时仅需1.567 V的电池电压，优于其纯相对应物和最近报道的基于双功能催化剂的器件。此外，这种CoP-Co P@PC/PG||CoP-Co P@PC/PG器件在OWS方面表现出出色的稳定性。这项工作可能为基于相工程优化TMPs纳米结构提供一些启示，并促进它们在OWS或其他可再生能源领域的应用。
