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The power conversion efficiency of solar cells is strongly impacted by an unwanted loss of charge carriers occurring at semiconductor surfaces and interfaces. Here the use of ion‐charged oxide nanolayers to enhance the passivation of silicon surfaces via the field effect mechanism is reported. The first report of enhanced passivation from rubidium and cesium ion‐charged oxide nanolayers is provided. The charge state and formation energy of ion‐charged silicon dioxide are calculated from first principles. Ion embedding is demonstrated and exploited to control the interface population of carriers and minimize electron‐hole pair recombination. The passivation quality directly improves with charge concentration, yet excess ions can produce detrimental interface states. An optimal ionic charge concentration of ≈1.5 × 1012 q cm−2 is deduced, and a recombination velocity and current density as low as 2.8 cm s−1 and 7.8 fA cm−2 are achieved at the Si‐SiO2 interface. Maximized charge is shown to provide efficiency improvements as high as 0.7% absolute. This work provides a unique route to enhance passivation without compromising the film synthesis, thus retaining the antireflection and hydrogenation film properties. As such, ion‐charged dielectrics provide complementary paths for surface and interface optimization in future single‐junction and tandem solar cells. [ABSTRACT FROM AUTHOR]

The production and performance of p‐type inversion layer (IL) Si solar cells, manufactured with an ion‐injection technique that produces a highly charged dielectric nanolayer, are investigated. It is demonstrated that the field‐induced electron layer underneath the dielectric can reach a dark sheet resistance of 0.95 kΩ sq−1 on a 1 Ω cm n‐type substrate, lower than any previously reported. In addition, it is shown that the implied open‐circuit voltage of a p‐type IL cell precursor with a highly charged dielectric is equivalent to that of a cell with a phosphorous emitter. In the cell precursor, light‐beam‐induced current measurements are performed, and the uniformity and performance of the IL is demonstrated. Finally, simulations are used to explain the physical characteristics of the interface leading to extremely low sheet resistances, and to assess the efficiency potential of IL cells. IL cells are predicted to reach an efficiency of 24.5%, and 24.8% on 5/10 Ω cm substrates, by replacing the phosphorous emitter with a simpler manufacturing process. This requires a charge density of beyond 2 × 1013 cm−2, as is demonstrated here. Moreover, IL cells perform even better at higher charge densities and when negative charge is optimized at the rear dielectric. [ABSTRACT FROM AUTHOR]

A general solution-based approach to deintercalate zero-valent tin and copper from two-dimensional layered chalcogenides is presented using a one-step comproportionation reduction-oxidation reaction. The reaction is performed between the intercalated zero-valent metal and high oxidation state metal cations (Sn4+ and Cu2+) dissolved in acetone. This chemistry is shown to work for a variety of layered chalcogenides with differing morphologies and crystallinity. Copper and tin are deintercalated from powders of MoS2, MoSe2, NbSe2, and WS2 and crystalline nanoribbons of Bi2Se3, In2Se3, and GeS. This chemistry achieves a general route to remove zero-valent tin and copper from 2D layered chalcogenides. [ABSTRACT FROM AUTHOR]