Electro-Materials Research Laboratory, Centre for Nanoscience and Technology, Pondicherry University, Puducherry - 605 014, India.
Nanoscale. 2019 Oct 3;11(38):17579-17589. doi: 10.1039/c9nr07060e.
Nickel selenide (NiSe) nanoparticles were grown on graphene nanosheets (GN) with different mass ratios to obtain their corresponding NiSe/GNx (x = 0.25 to 1.00) nanohybrids by a facile in situ hydrothermal process to integrate the advantages of the high specific surface area of graphene and the homogeneously immobilized catalytic sites of NiSe. The nanohybrid with a mass ratio of 1 : 0.50 (i.e., NiSe/GN0.50) exhibited higher electrocatalytic activity and electrolyte diffusion. Thus, NiSe/GN0.50 exhibited an improved photo-conversion efficiency (PCE) of 12% (η = 8.62%) compared to a standard Pt (η = 7.68%)-based dye-sensitized solar cell (DSSC). This improved PCE mainly originated from the catalytic ability of NiSe and the multiple interfacial electron transfer pathways of graphene, resulting in enhanced charge transfer and fast tri-iodide reduction kinetics at the counter electrode/electrolyte interface. The results obtained from the cyclic voltammetry (CV), electrochemical AC-impedance (EIS) and Tafel polarization studies validated the synergistic effects of NiSe and GN and the high potential of this nanohybrid as an efficient counter electrode (CE) for DSSCs.
镍硒化物（NiSe）纳米粒子在不同质量比的石墨烯纳米片（GN）上生长，通过简便的原位水热法获得相应的 NiSe/GNx（x = 0.25 至 1.00）纳米杂化物，以整合石墨烯的高比表面积和 NiSe 均匀固定的催化位点的优势。质量比为 1：0.50（即 NiSe/GN0.50）的纳米杂化物表现出更高的电催化活性和电解质扩散性。因此，与基于 Pt（η=7.68%）的标准染料敏化太阳能电池（DSSC）相比，NiSe/GN0.50 表现出提高的光电转换效率（PCE）为 12%（η=8.62%）。这种提高的 PCE 主要源于 NiSe 的催化能力和石墨烯的多个界面电子转移途径，导致在对电极/电解质界面处增强了电荷转移和快速三碘化物还原动力学。循环伏安法（CV）、电化学交流阻抗（EIS）和 Tafel 极化研究的结果验证了 NiSe 和 GN 的协同效应以及该纳米杂化物作为高效对电极（CE）用于 DSSC 的高潜力。
