Abstract：
Water splitting is a long-standing quest to material research for mitigating the global energy crisis. Despite high efficiency shown by several high cost noble metal containing electrocatalysts in the water splitting reaction, scientists are focused on alternate metal-free carbon or polymer based materials with comparable activity to make the process economical. In this article, we have strategically designed a noble metal-free thiadiazole (TDA) and triazine (Trz) linked porous organic polymer (TDA-Trz-POP) having N- and S-rich surface. Powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR), solid state 13C magic angle spinning nuclear magnetic resonance (MAS-NMR) and X-ray photoelectron spectroscopic (XPS) analyses have been performed to predict its probable framework structure. This scrunch paper type TDA-Trz-POP shows an extravagant potential for the hydrogen evolution reaction (HER) with a low overpotential (129.2 mV w.r.t. RHE for 10 mA cm-2 current density) and low Tafel slope (82.1 mV deg-1). Again, this metal-free catalyst shows oxygen evolution reaction (OER) at 410 mV overpotential w.r.t RHE for 10 mA cm-2 current density with a lower Tafel slope of 104.5 mV deg-1. This bifunctional activity was further tested in two electrodes set-up under different pH conditions. The porosity seems to be a blessing in the electrocatalytic performance of this metal-free electrocatalyst material. Further, the mystery behind the activity of both HER and OER has been resolved through the density functional theory (DFT) analysis. This work provides an insight to the material scientists for low cost, metal-free material design for the efficient water splitting reaction.
摘要：
水分解是缓解全球能源危机的物质研究的长期追求。尽管在水分解反应中几种高成本的含贵金属的电催化剂显示出高效率，科学家们专注于替代无金属的碳或聚合物基材料具有可比的活性，使过程经济。在这篇文章中,我们战略性地设计了一种无贵金属的噻二唑（TDA）和三嗪（Trz）连接的多孔有机聚合物（TDA-Trz-POP），具有富N和S的表面。粉末X射线衍射(PXRD),傅里叶变换红外(FT-IR),已进行了固态13C幻角旋转核磁共振（MAS-NMR）和X射线光电子能谱（XPS）分析，以预测其可能的框架结构。这种硬纸型TDA-Trz-POP显示出析氢反应（HER）具有低过电位（10mAcm-2电流密度为129.2mVw.r.t.RHE）和低Tafel斜率（82.1mVdeg-1）。再一次,这种无金属催化剂在10mAcm-2电流密度下，在410mV超电势w.r.tRHE下显示出析氧反应（OER），较低的Tafel斜率为104.5mVdeg-1。在不同pH条件下在两个电极设置中进一步测试这种双功能活性。孔隙率似乎是这种不含金属的电催化剂材料的电催化性能的祝福。Further,通过密度泛函理论（DFT）分析，解决了HER和OER活性背后的奥秘。这项工作为材料科学家提供了低成本的见解，无金属材料设计，用于高效的水分解反应。
