Advanced engineering of inorganic semiconductor nanowires: Materials-by-design for next-generation green energy technologies

Inorganic semiconductor nanowires (NWs) provide an unusually versatile platform for green-energy technologies because composition, crystal phase, defects, interfaces, morphology, and dimensionality can be engineered across multiple length scales. This review critically examines how these coupled design variables govern charge generation and transport, surface recombination, catalytic activity, ion diffusion, thermal transport, and operational stability. Rather than cataloguing individual materials, we identify transferable structure–property–performance relationships across photovoltaics, photoelectrochemical water splitting, photocatalysis, electrochemical energy storage, and thermoelectric conversion. A central conclusion is that nanoscale advantages are intrinsically conditional: reduced dimensions can enhance light trapping, carrier collection, reaction kinetics, and strain accommodation, but simultaneously intensify surface recombination, interfacial instability, defect sensitivity, and integration losses. We therefore evaluate competing engineering strategies in terms of these trade-offs and their implications for device-scale performance, durability, manufacturability, and sustainability. Recent advances in operando characterization, multiscale simulation, density functional theory, machine learning, and active learning are further assessed as tools for connecting synthesis conditions with experimentally validated material states and functional performance. Particular attention is given to the remaining gap between idealized computational predictions and structurally complex experimental NWs. Finally, we identify reproducibility, standardized data, device integration, scalable manufacturing, long-term stability, and uncertainty-aware human-supervised automation as critical requirements for translating semiconductor NWs from laboratory optimization toward deployable green-energy systems.