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Lithium–sulfur (Li–S) batteries have been regarded as promising candidates for current energy-storage technologies due to their remarkable advantages in energy density and theoretical capacity. However, one of the daunting challenges remained for advanced Li–S systems thus far deals with the synchronous suppression of polysulfide (LiPS) shuttle and acceleration of redox kinetics. Herein, a cooperative interface bridging adsorptive V2O3and conductive graphene is constructed in-situby virtue of direct plasma-enhanced chemical vapor deposition (PECVD), resulting in the design of a novel V2O3-graphene hybrid host to synergize the LiPS entrapment and conversion. The redox kinetics and electrochemical performances of thus-derived cathodes were accordingly enhanced owing to the smooth adsorption-diffusion-conversion of LiPSs even at a sulfur mass loading of 3.7 mg cm–2. Such interfacial engineering offers us a valuable opportunity to gain insight into the comprehensive regulation of LiPS anchoring ability, electrical conductivity and ion diffusive capability in hybrid hosts on suppressing the LiPS shuttle and propelling the redox kinetics. Our devised PECVD route might pave a new route toward the facial and economic design of hetero-phased multi-functional hosts for high-performance Li–S systems.

Coupling piezoelectric and plasmonic effect to tune the separation and migration of photogenerated charge carriers remains the key to improving the visible-light-driven photoelectrochemical energy conversion performance. Herein, we report the rational design of Ag/BiFeO3fibrous heterostructures (Ag/BFO) with the synergy of piezoelectric field and localized surface plasmon resonance (LSPR) modulation. Piezo-response force microscopy detection shows that the Ag2/BFO (AgNO3dosage: 2 mL) heterostructure has the optimal piezoelectric properties (29.3 pm at −7.53 V). As a demonstration, the degradation of methyl orange and methylene blue is used to evaluate the photoelectric conversion performance of the prepared samples. The results indicate that the ultrasonic-driven and visible-light-driven Ag2/BFO sample presents significantly enhanced activity, in which the piezoelectric field inside the BFO can further promote the directional migration and separation of photogenerated charge carriers induced by the LSPR effect of Ag nanoparticles. This work offers an intriguing solution toward the rational design of advanced materials targeting direct conversion of solar light into chemical energy.

The detrimental shuttle effect and retarded sulfur reaction kinetics in lithium–sulfur (Li–S) chemistry mainly lead to inferior electrochemical performances, posing a fatal threat to the practical application of Li–S batteries. Herein, porous N-doped Ti3C2MXene (P-NTC) has been realized by a scalable sacrificial templating route, resulting in the rational design of active electrocatalyst for Li–S chemistry. Benefiting from the superb electron conductivity, large surface area and strong interaction with lithium polysulfides (LiPSs), P-NTC can trigger the surface-mediated redox reaction of LiPSs. Moreover, the homogenous nitrogen doping on Ti3C2gives rise to enhanced interfacial interaction with Li atom and lowered dissociation barrier for Li2S. Therefore, the template-derived P-NTC not only acts as an effective LiPS immobilizer but also serves as a multifunctional electrocatalyst to propel the nucleation and decomposition of Li2S in discharge and charge processes, respectively. As expected, thus-fabricated S/P-NTC cathode maintains a low capacity decay of only 0.033% per cycle at 2.0 C over 1200 cycles. In further contexts, our ability to tune the sulfur mass loadings enables fabricated cathodes to harvest a high areal capacity of 9.0 mAh cm−2, holding great promise in future practical applications.