Vapor-liquid-solid growth of unconventional nanowires

TL;DR

This review compares vapor-liquid-solid growth mechanisms of conventional semiconductor nanowires with non-conventional types like oxides and chalcogenides, highlighting challenges and future opportunities for deterministic synthesis.

Contribution

It categorizes and analyzes the literature on VLS growth of non-conventional nanowires, identifying key differences and mechanistic factors affecting synthesis development.

Findings

VLS growth of non-conventional nanowires faces unique mechanistic challenges.

Precursor chemistry and seed dynamics significantly influence nanowire synthesis.

Insights from conventional nanowire growth can inform progress in non-conventional systems.

Abstract

Vapor liquid solid (VLS) growth is one of the most widely used routes for nanowire synthesis. For conventional semiconductor nanowires, here we refer to group IV and III-V systems, decades of work have established VLS growth across diverse vapor-phase methods and enabled substantial control over morphology, crystal phase, and structural modulation. In contrast, comparable deterministic control has not yet been achieved for many non-conventional nanowire classes, including oxides, carbides, and chalcogenides, despite their predicted functional properties and broad application potential. Here we survey and categorize the literature on VLS and VLS-related synthesis of these non-conventional nanowires, highlighting key similarities and differences relative to the group IV and III-V baseline. We analyze mechanistic and potential factors that underlie the lag in synthesis development, including constraints associated with precursor's chemistry and delivery, seed particle composition and dynamics, and competing non-catalytic nucleation and growth pathways. The review is grouped into three main sections, according to the order in which each step takes place during a nanowire growth process, namely precursor delivery, seed particle formation, and nucleation and growth. Each section starts with a brief discussion of what has been achieved in group IV and III-V nanowires as a baseline, followed by similar as well as unique aspects in other material classes. Each section concludes with challenges and opportunities, where we discuss how insights developed in one nanowire system can inform progress in others, ultimately paving the way for more deterministic synthesis and integration of complex one-dimensional nanomaterials.