Abstract Bottom‐up approaches to synthesising electronic materials from solution-phase precursors to form functional thin-films can enable electronics with tailorable, on-demand properties to be built in flexible forms and ubiquitously deployed onto arbitrary host objects. Such flexible electronics present a sizeable market that is projected to be on the order of 100’s of billions in 2030 (IDTechEx). Despite the tremendous strides made over the last two decades, thin-film devices grown from solutions are still much inferior to the vacuum-processed counterparts. This is primarily due to a large number of defects existing in solution-grown films that adversely induce various types of energy losses during carriers’ transport, hence resulting in ineffective carrier percolation pathways and further impeding solution-grown devices from achieving their optimal functionality. In this talk, I will show how I utilised device and material engineering to build robust electronic and optoelectronic devices. I will first introduce a hybrid lamellar channel architecture that is fabricated using oxide and organic materials from precursor solutions at plastic-compatible processing temperature [1]. The introduction of advantageous organic functional groups can effectively passivate oxygen defects and prevent their mobilisations, enabling oxide thin-film transistors with record high operational stability. Following this, I will describe a geometric engineering strategy using solid-state hetero-oxide transistors for real-time detection of liquid-phase biomolecules [2]. Selective detection is enabled by suitable analyte receptors tethered on the oxide surface. Recently, I purposed this sensor for the detection of SARS-CoV-2 spike protein and demonstrated attomolar sensitivity with an ultrahigh dynamic range. Lastly, I will discuss the potential of metal-halide perovskite photovoltaics for powering indoor electronic devices and forming tandem cells with Si by addressing the biggest concern in the perovskite community – long-term stability [3]. I will show how an ionic additive can effectively retard cell degradation and help achieve unprecedentedly high operational stability. Looking forward, perfecting our engineering approaches can largely mitigate disadvantageous material properties and render the practicality of low-cost solution-grown functional materials for a wide range of electronic, optoelectronic and energy applications with economically viable manufacturing solutions. Reference [1] Y.-H. Lin et al., Nature Electronics 2, 587-595 (2019). [2] “Arab institutions ramp up COVID-19 research”, Nature Middle East. [3] Y.-H. Lin et al., Science 369, 96-102 (2020). - Rendering the Practicality of Solution-Grown Materials for Ubiquitous Electronics and Energy Harvesting