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AlGe2P achieves the fastest electronic and Li-ion conductivities among Al3Ge2P3, AlGe2P, AlGe6P and Ge as verified by first-principles calculations and experimental validations, thus providing superior Li-storage properties.

In this study, the reaction mechanism and electrochemical properties of carbon-supported PtSn nanomaterials including nanoparticles and nanowires (NWs) toward the oxygen reduction reaction (ORR) have been investigated computationally and experimentally. Segregation energy calculations were applied to screen the unique thermodynamic stability of PtSn under ORR operation. Materials chemistry processing was further utilized to tailor the morphologies of PtSn NWs that have shown promoted ORR stability when compared to Pt NWs (24 vs. 83% decay during durability tests of 10 000 cycles). Additionally, these PtSn NWs with a Pt rich inner core and an Sn rich outer shell structure also showed an enhancement in ORR activity from electrochemical tests. The enhanced performance, which has been rationalized by computation and various experimental techniques of high resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and X-ray absorption spectroscopy, can be attributed to Sn and its oxides inducing change of electronic structures and the morphological effects, which not only reduce oxophilicity and the d-band center of surface Pt but also stabilize the structure during the durability test.

Ru–Pd nanoparticles (NPs) with Pt atomic cluster modification were synthesized using polyol reactions with a sequence design. Such modification resulted in the formation of Ru in the inner core and Pd on the outer shell structure (Rucore–Pdshell) via transmetalation between the Pt ion and Pd atom followed by thermal reduction. The Pt modified Rucore–Pdshell NPs improve the on-set potential by 0.041 volt and reduce Pt loading to less than ∼2%, as compared with that of carbon supported Pt NPs. For the optimum case, the MA (current degradation) of Ru–Pd NPs is improved (suppressed) by ∼345% (18.1%) in the accelerated degradation test (ADT) at 0.85 volt (vs. RHE) for 5000 cycles by intercalating Pt clusters (2 to 9 at%) in the NP surface. These improvements are attributed to the electron localization and reinforcement by surface Pt clusters, which facilitated the oxygen reduction activity and chemical durability of NPs.

In this study, we have investigated the oxygen reduction reaction (ORR) activity and durability of Co-based catalysts mechanistically. CoPt/C catalysts with a Pt loading of 7 wt% and Au modification have been prepared and shown excellent ORR performance. The various as-prepared CoPt/C and CoPtAu/C catalysts have about 2.6–9.2 times higher mass activity than commercial Pt/C. The mechanistic insight obtained by density functional theory calculations has shown that the enhanced activity is attributable to the fact that Co-based catalysts can easily dissociate surface O2* without the high-barrier protonation step and efficiently remove the dissociated O*. The improved stability, 1000th decay = 14.6%, corresponds to the fact that the core Au can resist the shrinkage of surface Pt during the accelerated durability test.

Correction for ‘Local heterojunctions of atomic Pt clusters boost the oxygen reduction activity of Rucore@Pdshell nanocrystallites’ by Jeng Han Wang et al., J. Mater. Chem. A, 2016, 4, 17848–17856.