For practical H 2 production via photoelectrochemical (PEC) water splitting, a proper nanostructure strategy allowing sufficient light absorption and effective charge carrier transport is of immense importance. In this study, via the unique sequential use of two different molecular inks, a bilayer nanostructure for a photocathode composed of vertically oriented nanorods Sb 2 Se 3 on top of a bottom compact Sb 2 Se 3 layer is produced. The hierarchical nanorod bilayer structure possesses light-trapping ability owing to the scattering effect, resulting in the enhancement of light absorption. The bilayer Sb 2 Se 3 photocathode also exhibits better charge-transport capability owing to the synergetic effects of the favorable crystallographic orientation and the enlarged surface area of the vertically aligned nanorods. The bilayer Sb 2 Se 3 photocathode achieves a photocurrent density of nearly 30 mA cm −2 at 0 V vs the reversible hydrogen electrode. This observation implies that the proposed solution-processed Sb 2 Se 3 -based hierarchical bilayer structure is a promising candidate for an efficient PEC water splitting tandem device.

Although tin monosulfide (SnS) is one of the promising earth-abundant semiconducting materials for photoelectrochemical water splitting, the performance of SnS photocathodes remains poor. Herein, we report a stepwise approach for the fabrication of highly efficient photocathodes based on SnS nanoplates via elaborate modulation of molecular solutions. It is demonstrated that phase-pure SnS nanoplates without detrimental secondary phases (such as SnS 2 and Sn 2 S 3 ) can be readily obtained by adjusting the amounts of Sn and S in the precursor solution. Additionally, the orientation of SnS nanoplates is controlled by implementing different types of SnS seed layers. The orientations of the SnS seed layers are changed according to the molecular shapes of the Sn− S bonds in the molecular solutions, depending on the relative nucleophilicity of the molecular moieties formed by specific thiol−amine reactions. The molecular Sn−S sheets in the seed ink was obtained by the reaction in a solvent mixture of thiogylcolic acid and ethanolamine. By contrast, the short Sn−S molecular rods result from the reaction in a solvent mixture of 2-mercaptoethanol and ethylenediamine. Interestingly, the relatively short rodlike morphology of the SnS seed induces the growth of SnS nanostructures faceted by preferred ( 111) and (101) planes, leading to fast charge transport. With the formation of a proper band alignment with n-type CdS and TiO 2 , the preferred (111)-and (101)-oriented SnS nanoplatebased photocathode exhibited a photocurrent density of −19 mA cm −2 at 0 V versus a reversible hydrogen electrode, establishing a new benchmark for SnS photocathodes.

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As the demand for higher energy density in portable electronics and electric vehicles has increased, novel electrode materials with high reversible capacity have received significant research attention for breakthrough into next‐generation lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs). Tin monosulfide is a particularly promising anode material for both LIBs and SIBs due to its exceptional electrochemical properties, thus several strategies based on nanoengineered SnS/carbon composites (NSCs) have been introduced to improve the electrical and ionic conductivity and to reduce the volume change that occurs during cycling. However, to fully exploit the outstanding properties of NSCs, the crystallographic orientation of anisotropic SnS should be optimized. Herein, vertically aligned SnS nanoplate arrays (VA‐SnS@C) with preferred (111) and (101) orientations covered by carbon layers are fabricated using a facile spin‐coating method followed by a simple glucose solution bath. The as‐fabricated (111)‐oriented VA‐SnS@C anode demonstrates better electrochemical performance than does the (040)‐oriented planar SnS (PL‐SnS@C) anode, illustrating the critical role of the crystallographic orientation in NSCs. The superior electrochemical performance of the VA‐SnS@C anode demonstrates that this facile approach harnesses the synergistic effects of orientation‐controlled SnS and versatile carbon layers, which is crucial to design high‐performance anodes for next‐generation LIBs and SIBs.

The traditional photoelectrochemical (PEC) tandem configuration of hydrogen evolution reaction and oxygen evolution reaction (OER) demands a considerable potential of 1.8 V due to theoretical water splitting potential as well...