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The lumping kinetic approach was used to model the hydrotreatment of full-range middle temperature coal tar at various operating conditions. A seven-lump model, which contains 20 constants, was proposed according to the reaction mechanism and a series of assumptions. The kinetic parameters were estimated by means of applying a variable metric method (BFGS). The results were validated by a series of further experiments. The effects of hydrogen partial pressure, LHSV (liquid hourly space velocity, h−1) and bed temperature on the performance of hydrotreatment were also investigated. Comparisons between experimental and calculated data showed good agreement.

Lithiophilic hosts hold exciting prospects to tackle the challenges of the dendrite growth and volume expansion of Li metal anode. However, insight into the structure of lithiophilic sites on impacting Li deposition which determines the reliability of electrode yet remains elusive. Here, based on nonlinear phase-field simulations, we show that the Li-ion flux in the electrolyte and current density on the electrode surface are closely related to the dispersity of lithiophilic sites. Taking ZnO as an example, we also experimentally demonstrate that host with densely and homogenously distributed ZnO nanodots allows uniform Li nucleation and even Li deposition compared to its counterparts with separately dispersed and randomly coalesced morphologies. Consequently, symmetric cell with the well-designed anode delivers a long-term lifespan of 1300 h with a low overpotential of only 11 mV. Further coupling with a sulfurized polyacrylonitrile cathode, the full cell displays a steady capacity of 1120 mA h g−1for 800 cycles at 1 C and a superb rate capacity of 702 mA h g−1at 5 C. These findings correlate the structure of lithiophilic sites with the mesostructure evolution of Li during deposition, and would provide useful guidance for the host designs toward high-performance rechargeable Li batteries.

Electrocatalysts are considered the most promising candidates in ameliorating the slow kinetics of Li–S batteries (LSBs), however, the issue of insufficient catalytic capability remains to be addressed. Herein, we report an integrated catalytic network comprising graphitic carbon-encapsulated/bridged ultrafine NiCoP embedded in N, P-codoped carbon (GC-uNiCoP@NPC) as a highly competent catalyst for sulfur-based species conversions. By profiling the evolution map of Li–S chemistry via operando kinetic analyses, GC-uNiCoP@NPC is demonstrated to possess versatile yet efficient catalytic activity for sulfur reduction/evolution reactions, especially the rate-determining heterogeneous phase transitions. As a result, GC-uNiCoP@NPC enables high capacity and stable cycling of sulfur cathode under high areal loading and lean electrolyte. Moreover, pouch cells assembled under practical conditions present promising performance with a specific energy of 302 Wh kg–1. This work not only conceptually expands the catalyst design for LSBs but also provides a comprehensive insight into the catalyst performance for Li–S chemistry.