2026-10-13T21:02:04Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34024834 2026-09-29T15:38:55Z category_1 category_4 category_915 category_14 category_21 category_873 category_502 category_734 category_931 category_61 category_69 portal_63 item_type_6 month_year_09_2026

Hierarchical Morphology Engineering of Silicon Micropillars Dictates Interfacial Kinetics for Room-Temperature Hydrogen Sensing Yuanping Zhang (309388) Mengxin Liu (10182564) Ran Xiong (719629) Xianwu Xu (19934928) Hongbo Wang (587749) Caijiang Lu (25137703) Bingjun Yu (2098909) Linmao Qian (1567639) Zhi-Jun Zhao (287192) Biophysics Biochemistry Physical Sciences not elsewhere classified Molecular Biology Biotechnology Chemical Sciences not elsewhere classified Astronomical and Space Sciences not elsewhere classified Biological Sciences not elsewhere classified Information Systems not elsewhere classified Developmental Biology Inorganic Chemistry offers fundamental insights dominated physicochemical interactions assisted chemical etching traditional smooth micropillars smps counterpart  enhanced sensing behavior assisted interfacial transport low detection limit chip silicon architectures temperature hydrogen sensing hierarchical morphology engineering 2 </ sub hmps sensor achieved hierarchical morphology hierarchical architectures traditional top smps ). silicon substrates sensor exhibits interfacial reactions interfacial kinetics work establishes versatile paradigm toward 1 temperature h step metal precise construction optimized pd morphological bottlenecks modified hmps humidity conditions highly desirable fold enhancement employed pd constructing complex concept model anomalous humidity amplifying surface 200 ppb The precise construction of three-dimensional (3D) hierarchical architectures on silicon substrates is highly desirable for amplifying surface-dominated physicochemical interactions. However, traditional top-down microfabrication typically yields inherently smooth sidewalls, restricting active site density and causing the “premature saturation” of interfacial reactions. Herein, we report a controllable morphology engineering strategy via one-step metal-assisted chemical etching (MACE) to fabricate hierarchical silicon micropillars (HMPs) with in situ sculpted nanoscale rough sidewalls. To elucidate the impact of this hierarchical morphology on interfacial kinetics, we employed Pd-modified HMPs for room-temperature H₂ sensing as a proof-of-concept model. This custom architecture effectively bypasses the morphological bottlenecks of traditional smooth micropillars (SMPs). The optimized Pd/HMPs sensor achieved a response of up to 628% toward 1% H₂a > 6-fold enhancement over its SMPs counterpartwith a low detection limit of 200 ppb. Intriguingly, the sensor exhibits an anomalous humidity-enhanced sensing behavior under low-humidity conditions, revealing a unique synergistic mechanism jointly governed by local surface charge modulation and proton-assisted interfacial transport. This work establishes a versatile paradigm for constructing complex on-chip silicon architectures and offers fundamental insights into how morphology governs interfacial kinetics. 2026-09-29T00:00:00Z Text Journal contribution 10.1021/acs.langmuir.6c03618.s001 https://figshare.com/articles/journal_contribution/Hierarchical_Morphology_Engineering_of_Silicon_Micropillars_Dictates_Interfacial_Kinetics_for_Room-Temperature_Hydrogen_Sensing/34024834 CC BY-NC 4.0