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This paper designs and optimizes a new structure hybrid material B‐pillar assembly. Establish a finite element analysis model for the side impact test of an electric vehicle to verify the model's accuracy. Construct a finite element model of the hybrid material B‐pillar assembly. Combined with the static performance analysis of the B‐pillar, the laminate design of the carbon fiber composite B‐pillar reinforcement plate and optimization. For the outer and inner panels of the B‐pillar, the surrogate model method and the multiobjective optimization method are combined to set 11 design variables and 13 responses. The optimal Latin hypercube design method was used to randomly sample each design variable and fit the radial basis function (RBF) approximate model. The modified second‐generation non‐dominated sorting genetic algorithm (MNSGA‐II) was used to carry out multiobjective optimization of the mixed material B‐pillar assembly, and the multicriteria decision‐making method was used to obtain the optimal solution for the Pareto solution set. A drop weight impact test was performed on the hybrid material B‐pillar assembly. The results showed that the peak collision force of the hybrid material B‐pillar was reduced by 43.7% compared with the original steel B‐pillar, the specific energy absorption was increased by 17.5%, and the side impact safety performance was better. After optimization, the weight of the mixed material B‐column was reduced by 26.44%. The improvement rates of the intrusion amount at P2 and the intrusion speed at P1 were 23.99% and 0.63%, respectively, and the lightweight effect and side impact safety were significantly improved. Highlights: The finite element analysis parameters of carbon fiber composite materials were constructed through experiments, and the basis for simulation analysis under various working conditions of the B‐pillar based on performance‐driven optimization was established.A hybrid material B‐pillar design method is proposed, which consists of a variable‐thickness high‐strength steel B‐pillar outer plate, a variable‐thickness high‐strength steel B‐pillar inner plate, and a carbon fiber composite B‐pillar reinforcement plate.The super layer of the carbon fiber composite B‐pillar reinforcement plate was optimized and the laying plan of the carbon fiber composite B‐pillar reinforcement plate was determined.Performance‐driven optimization is adopted to realize the collaboration of multilevel design and optimization methods such as B‐pillar conceptual design, detailed design, and multiobjective optimization.A modified NSGA‐II algorithm was proposed and combined with the multicriteria decision‐making method and the entropy‐weighted gray relation analysis method to determine the Pareto optimal solution and the optimal design scheme for the mixed material B‐pillar. [ABSTRACT FROM AUTHOR]

Fabricating metal boride heterostructures and deciphering their interface interaction mechanism on accelerating polysulfide conversion at atomic levels are meaningful yet challenging in lithium–sulfur batteries (LSBs). Herein, novel highly‐conductive and binary sulfiphilic NbB2‐MXene heterostructures are elaborately designed with spontaneous built‐in electric field (BIEF) via a simple one‐step borothermal reduction strategy. Experimental and theoretical results reveal that Nb and B atoms can chemically bond with polysulfides, thereby enriching chemical anchor and catalytic active sites. Meanwhile, the spontaneous BIEF induces interfacial charge redistribution to make more electrons transferred to surface NbB2 sites, thereby weakening its strong adsorption property yet accelerating polysulfide transfer and electron diffusion on hetero‐interface, so providing moderate polysulfide adsorb‐ability yet decreasing sulfur‐species conversion energy barriers, further boosting the intrinsically catalytic activity of NbB2‐MXene for accelerated bidirectional sulfur conversion. Thus, S/NbB2‐MXene cathode presents high initial capacity of 1310.1 mAh g−1 at 0.1 C, stable long‐term lifespan with 500 cycles (0.076% capacity decay per cycle) at 1 C, and large areal capacity of 6.5 mAh cm−2 (sulfur loading: 7.0 mg cm−2 in lean electrolyte of 5 µL mgs−1) at 0.1 C. This work clearly unveils the mechanism of interfacial BIEF and binary sulfiphilic effect on accelerating stepwise sulfur conversion at atomic levels. [ABSTRACT FROM AUTHOR]

Electrocatalytic reduction of CO2 (CO2RR) to formic acid (HCOOH) with high selectivity (>90%) and large current density (>100 mA cm−2) is highly challenging due to CO2 mass-transfer limitations. Herein, we in situ constructed 3D bismuth nanosheets@Cu nanowire core–shell nano-architectures on Cu foam (Cu@Bi NWs/Cu) as efficient electro-catalysts for CO2RR into HCOOH. The Cu@Bi NWs/Cu electrode achieves a large current density of 155.8 mA cm−2 with a HCOOH faradaic efficiency of 90.1% in a H-type cell. The superior activity is attributed to the large catalytic surface area related to the porous structure and high intrinsic activity induced by lattice defects on the preferential exposure of the Bi (110) facet. The atomic defects in the Bi (110) facet facilitate the entry of CO2 and realize four low-coordination atoms around the defected Bi atom, thereby generating more active sites and improving the catalytic performance. The presence of the Cu NW support significantly enhances the Bi reducibility of the Cu@Bi surface due to the partial electron transfer from Cu to Bi, thereby boosting the C-terminal hydrogenation of CO2. This work demonstrates an effective strategy to fabricate 3D porous core–shell nanoarchitectures consisting of a shell with numerous unsaturated sites on a highly-conductive core for efficient catalysis. [ABSTRACT FROM AUTHOR]