Owing to their abundance, low cost, and excellent functional properties and catalytic activity, transition metal phosphides (TMPs) have been proposed in a broad range of energy conversion technologies. However, their challenging synthesis and moderate electrical conductivity have limited their implementation in real applications. Here, we detail a simple procedure to grow fully dispersed nickel phosphide nanocrystals (NCs) with controlled size, phase, and composition on the surface of reduced graphene oxide (rGO). The resultant Ni_xP_y/rGO composites effectively combine a huge density of catalytically active sites from Ni_xP_y with the excellent conductivity of rGO, thus exhibiting highly improved electrocatalytic activities. Ni_xP_y/rGO composites were tested as the counter electrode (CE) in dye-sensitized solar cells (DSSCs), providing significantly improved performance over conventional Pt-based CEs. The incorporation of CEs based on Ni₁₂P₅/rGO composites allowed reaching a power conversion efficiency of up to 8.19%, well above those of DSSC-based Pt CEs (7.87%). According to density functional theory (DFT) calculations, the outstanding electrocatalytic activity of Ni₁₂P₅/rGO as a CE in DSSCs was associated with the exceptional I₃^– adsorption capacity. These results prove that Ni₁₂P₅/rGO is a promising candidate to replace Pt as a CE in DSSCs.

中文翻译：

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还原氧化石墨烯上原位生长的纳米磷酸镍单晶，具有可控制的尺寸和组成，作为染料敏化太阳能电池的对电极

由于其丰富，低成本，出色的功能特性和催化活性，过渡金属磷化物（TMP）已被广泛应用于能量转换技术中。然而，它们具有挑战性的合成和适度的电导率限制了它们在实际应用中的实施。在这里，我们详细介绍了在还原的氧化石墨烯（rGO）的表面上生长具有受控大小，相和组成的完全分散的磷化镍纳米晶体（NCs）的简单程序。将所得的Ni _X P _ý / RGO复合材料有效结合催化活性位点的一个巨大的密度选自Ni _X P _ÿ与RGO的优异的导电性，从而表现出极大提高的电活动。你在染料敏化太阳能电池（DSSC）中测试了_x P _y / rGO复合材料作为对电极（CE），与传统的基于Pt的CE相比，性能得到了显着改善。掺入基于Ni ₁₂ P ₅ / rGO复合材料的CE可以实现高达8.19％的功率转换效率，远高于基于DSSC的Pt CE的功率转换效率（7.87％）。根据密度泛函理论（DFT）计算，Ni的优秀的电催化活性₁₂ P ₅ / RGO在DSSC中一个CE与异常相关联的我₃ ^-的吸附能力。这些结果证明Ni ₁₂ P ₅/ rGO是替代Pt作为DSSC中CE的有希望的候选人。