School of Resources, Environment and Materials, Collaborative Innovation Center of Sustainable Energy Materials, State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, Guangxi University, Nanning, 530004, P. R. China.
Adv Sci (Weinh). 2023 Mar;10(9):e2207470. doi: 10.1002/advs.202207470. Epub 2023 Feb 3.
The targeted synthesis of manganese phosphides with target phase remains a huge challenge because of their various stoichiometries and phase-dependent physicochemical properties. In this study, phosphorus-rich MnP, manganese-rich Mn P, and their heterostructure MnP-Mn P nanoparticles evenly dispersed on porous carbon are accurately synthesized by a convenient one-pot heat treatment of phosphate resin combined with Mn . Moreover, their electrochemical properties are systematically investigated as sulfur hosts in lithium-sulfur batteries. Density functional theory calculations demonstrate the superior adsorption, catalysis capabilities, and electrical conductivity of MnP-Mn P/C, compared with MnP/C and Mn P/C. The MnP-Mn P/C@S exhibits an excellent capacity of 763.3 mAh g at 5 C with a capacity decay rate of only 0.013% after 2000 cycles. A phase evolution product (MnS) of MnP-Mn P/C@S is detected during the catalysis of MnP-Mn P/C with polysulfides redox through in situ X-ray diffraction and Raman spectroscopy. At a sulfur loading of up to 8 mg cm , the MnP-Mn P/C@S achieves an area capacity of 6.4 mAh cm at 0.2 C. A pouch cell with the MnP-Mn P/C@S cathode exhibits an initial energy density of 360 Wh kg .
由于其各种化学计量比和依赖于相的物理化学性质，目标合成具有目标相的磷化锰仍然是一个巨大的挑战。在这项研究中，通过将磷酸盐树脂与 Mn 进行一锅热处理，精确合成了富磷 MnP、富锰 MnP 和它们的异质结构 MnP-MnP 纳米粒子，均匀分散在多孔碳上。此外，还系统地研究了它们作为锂硫电池中硫主体的电化学性能。密度泛函理论计算表明，与 MnP/C 和 MnP/C 相比，MnP-MnP/C 具有优越的吸附、催化能力和电导率。MnP-MnP/C@S 在 5 C 时表现出优异的容量为 763.3 mAh g，在 2000 次循环后，容量衰减率仅为 0.013%。通过原位 X 射线衍射和拉曼光谱检测到 MnP-MnP/C 与多硫化物氧化还原反应中 MnP-MnP/C@S 的相演化产物（MnS）。在高达 8 mg cm 的硫负载下，MnP-MnP/C@S 在 0.2 C 时实现了 6.4 mAh cm 的面积容量。具有 MnP-MnP/C@S 阴极的软包电池显示出初始能量密度为 360 Wh kg。
