Jamdagni, PoojaKumar, AshokSrivastava, SunitaPandey, RavindraTankeshwar, K.2024-01-212024-08-132024-01-212024-08-132022-09-011463907610.1039/d2cp02549chttp://10.2.3.109/handle/32116/3726The highly efficient photocatalytic water splitting process to produce clean energy requires novel semiconductor materials to achieve a high solar-to-hydrogen energy conversion efficiency. Herein, the photocatalytic properties of anisotropic ?-PtX2 (X = S, Se) and Janus ?-PtSSe monolayers were investigated based on the density functional theory. The small cleavage energy for ?-PtS2 (0.44 J m?2) and ?-PtSe2 (0.40 J m?2) endorses the possibility of mechanical exfoliation from their respective layered bulk materials. The calculated results revealed that the ?-PtX2 monolayers have an appropriate bandgap (?1.8-2.6 eV) enclosing the water redox potential, light absorption coefficient (?104 cm?1), and exciton binding energy (?0.5-0.7 eV), which facilitates excellent visible-light-driven photocatalytic performance. Remarkably, the inherent structural anisotropy leads to an anisotropic high carrier mobility (up to ?5 � 103 cm2 V?1 S?1), leading to a fast transport of photogenerated carriers. Notably, the required small external potential to realize hydrogen evolution reaction and oxygen evolution reaction processes with an excellent solar-to-hydrogen energy conversion efficiency for ?-PtSe2 (?16%) and ?-PtSSe (?18%) makes them promising candidates for solar water splitting applications. � 2022 The Royal Society of Chemistry.en-USAnisotropyBinding energyDensity functional theoryEnergy conversion efficiencyLightLight absorptionPhotocatalytic activityRedox reactionsSemiconductor materialsSolar power generationWater absorptionClean energyDensity-functional-theoryEnergy conversion efficiencyHydrogen EnergyMechanical exfoliationPhotocatalytic propertyPhotocatalytic water splittingSolar-to-hydrogenSplitting processMonolayersArticlehttp://xlink.rsc.org/?DOI=D2CP02549C