The focus of this thesis is on developing two next-generation inorganic materials for thin-film device applications, namely photovoltaics and thin-film transistors. Both of these device applications are crucial in today’s technology-based society with photovoltaics enabling sustainable generation of electricity whilst advancements in thin-film transistors allow for development of low-power, efficient electronic devices. BiOI, a non-toxic, perovskite-inspired material is investigated for photovoltaics (PVs) whilst Cu₂O, with a reasonably high predicted hole mobility is developed for p-type thin-film transistors (TFTs). These novel materials are fabricated with scalable processing techniques which enable lower manufacturing costs and improve energy efficiency. In the first results chapter, the suitability of non-toxic BiOI as a photovoltaic material is investigated. Dense BiOI films grown by thermal chemical vapour deposition (CVD) incorporated into an all-inorganic ITO/NiO_x/BiOI/ZnO/Al stack demonstrate high external quantum efficiencies (80% at 450 nm wavelength). However, the 1.9 eV band gap of BiOI is not matched to terrestrial solar spectra; the PVs achieve 1.8% power conversion efficiency. Owing to improved spectral matching with indoor light spectra, BiOI devices improve in efficiency to 4.37% under 1000 lux white light emitting diode indoor illumination, and millimetre-area BiOI devices are sufficient to power novel carbon nanotube inverters. The factor limiting further efficiency gains is downwards band-bending at the BiOI/NiO_x interface owing to NiO_x having a lower work function. In the second chapter, MoS₂ is investigated as an alternative to NiO_x where the work function of MoS₂ is tuned through oxygen plasma treatment to increase its work function. The experimental examination of defect tolerance of BiOI is conducted in chapter three. BiOI films are vacuum-annealed to induce surface composition changes. Large changes in surface atomic fractions (reduction in iodine and bismuth by 40% and 5% respectively, and increase in oxygen by >45%) are observed. These significant changes do not affect the electronic and optoelectronic properties, in contrast to traditional covalent semiconductors. The applicability of low-temperature (≤ 200 °C) atmospheric pressure spatial atomic layer deposited (AP-SALD) Cu₂O for use in p-type TFTs is explored in chapter four. The performance of AP-SALD Cu₂O is comparable to atomic layer deposition (ALD) grown Cu₂O with an I_ON/I_OFF ratio of 10³, and field-effect mobility between 10^-4 - 10^-3 cm²·V^-1·s^-1, illustrating the potential of AP-SALD grown films for integration with flexible substrates.