Nanomaterials Beyond Silicon: Graphene, Quantum Dots and Perovskite Thin Films as Pillars of India's Digital and Green Future

Abstract The rapid evolution of information technology and the global transition toward low-carbon energy systems are exposing important limitations in relying exclusively on conventional silicon-based platforms. Nanomaterials provide a complementary route because their electronic, optical, mechanical and interfacial properties can be engineered at dimensions where quantum confinement, two-dimensional transport and defect/interface effects become technologically useful. This review critically examines three material families—graphene, semiconductor quantum dots and metal-halide perovskite thin films—as representative pillars of a post-silicon and low-carbon technology landscape. Graphene is considered for high-mobility sensing, transparent and flexible electronics, photodetection and energy storage; quantum dots for spectrally tunable optoelectronics, displays, photodetectors and photovoltaic light harvesting; and perovskite thin films for lightweight photovoltaics, tandem solar cells and multifunctional optoelectronic devices. Recent literature indicates rapid gains in perovskite photovoltaic efficiency and stability engineering, while commercialization of graphene and quantum-dot technologies is progressing more selectively and remains constrained by integration, lifetime, materials and manufacturing issues. The review uses a literature-based comparative framework rather than claiming new experimental measurements. The analysis identifies scalability, long-term stability, environmental safety, lifecycle management and integration with existing manufacturing infrastructure as common barriers. For India, the strategic opportunity lies not simply in replacing silicon, but in combining silicon with emerging nanomaterials to create advanced sensors, displays, energy harvesters and tandem photovoltaic systems. Such a materials ecosystem can support digital infrastructure, renewable-energy deployment, domestic advanced manufacturing and the longer-term technological objectives associated with Viksit Bharat 2047. Future progress will depend on reproducible synthesis, sustainable processing, device-level reliability, responsible materials management and stronger links between laboratory research and scalable manufacturing.