Altan, Aslihan AnterBerktas, ZeynepKaymak, NuriyeYildiz, MustafaDi Bartolomeo, AntonioOrhan, Elif2026-02-032026-02-0320251750-0443https://doi.org/10.1049/mna2.70012https://hdl.handle.net/20.500.12428/34772This study reports the fabrication and temperature-dependent electrical characterization of a heterojunction formed by lanthanum(III) hydroxide nanoparticles doped with polyethyleneimine-functionalised nitrogen-doped graphene quantum dots (La(OH)3NPs/PEI N-GQDs) on n-type silicon (n-type Si). The heterostructure exhibits diode-like behaviour in the 77-400 K temperature range, with rectification exceeding two orders of magnitude and increasing as the temperature decreases, reaching an exceptionally high value above 10(5) at 77 K. Temperature-dependent diode parameters, including barrier height, series resistance, and ideality factor, are extracted using the thermionic emission model, revealing that barrier height increases and ideality factor decreases with rising temperature. These trends, along with significant deviations from the ideal Richardson behaviour of Schottky diodes, are effectively explained by the Werner-G & uuml;ttler model, which attributes them to Gaussian spatial inhomogeneities of the barrier arising from interface states and nanocomposite-induced fluctuations. This study highlights the robust rectifying behaviour, excellent cryogenic performance, and wide-temperature applicability of the La(OH)3NPs/PEI N-GQDs on the Si heterostructure, establishing it as a promising platform for low-power diode applications under extreme thermal conditions.eninfo:eu-repo/semantics/openAccessheterojunctiongraphene quantum dotslanthanum hydroxide nanoparticlescryogenic rectificationbarrier inhomogeneityArticle20110.1049/mna2.70012Q3WOS:0016114918000012-s2.0-105021380721Q3