Search

Efficient evolution of hydrogen through electrocatalysis at low overpotentials holds tremendous promise for clean energy. Herein, a highly active and stable MoS2 electrocatalyst is supported on reduced graphene oxide-modified carbon nanotube/polyimide (PI/CNT-RGO) film for hydrogen evolution reaction (HER). The PI/CNT-RGO film allows the intimate growth of MoS2 nanoparticles on its surface. The nanosize and high dispersion of MoS2 nanoparticles provide a vast amount of available edge sites and the coupling of RGO and MoS2 enhances the electron transfer between the edge sites and the substrate, greatly improving the HER activity of PI/CNT-RGO-MoS2 film. The MoS2 with a smaller loading less than 0.04 mg cm−2 on the PI/CNT-RGO film exhibits excellent HER activities with a low overpotential of 0.09 V and large current densities, as well as good stability. The Tafel slope of 61 mV dec−1 reveals the Volmer-Heyrovsky mechanism for HER. Thus, this work paves a potential pathway for designing efficient MoS2-based electrocatalysts for HER. [ABSTRACT FROM AUTHOR]

Herein, a 2D SnS2 electron transporting layer is reported via self‐assembly stacking deposition for highly efficient planar perovskite solar cells, achieving over 20% power conversion efficiency under AM 1.5 G 100 mW cm−2 light illumination. To the best of the authors' knowledge, this represents the highest efficiency that has so far been reported for perovskite solar cells using a 2D electron transporting layer. The large‐scaled 2D multilayer SnS2 sheet structure triggers a heterogeneous nucleation over the perovskite precursor film. The intermolecular Pb⋅⋅⋅S interactions between perovskite and SnS2 could passivate the interfacial trap states, which suppress charge recombination and thus facilitate electron extraction for balanced charge transport at interfaces between electron transporting layer/perovskite and hole transporting layer/perovskite. This work demonstrates that 2D materials have great potential for high‐performance perovskite solar cells. Large‐scaled sheet structured 2D multilayer SnS2 triggers heterogeneous nucleation over the perovskite precursor film, bringing in balanced electron and hole transport at interfaces between electron transporting layers/perovskite and perovskite/hole transporting layer, and suppressing interfacial charge recombination, achieving the highest 20.12% power conversion efficiency that has so far been reported for perovskite solar cells using a 2D electron transporting layer. [ABSTRACT FROM AUTHOR]