We report a push-pull BODIPY-based dye functionalised with an electronegative SF5 group at the meso position for applications in photocathodes in tandem dye-sensitized solar cells (DSSCs). The push-pull character enhances charge-transfer from the mesoporous NiO cathode surface towards the redox mediator. A Knoevenagel condensation reaction was used to introduce the carboxylic acid to anchor the dye to the oxide surface, via a styryl linker which increases the conjugation in the molecule and shifts the absorption to the red. The room-temperature synthesis and high yields, make the dye promising for manufacture on a large scale. The dye was applied in p-DSSCs giving a power conversion efficiency (0.066%), a short circuit photocurrent (J SC) of 3.84 mA cm-2, open circuit voltage (V OC) of 58 mV and fill factor of 30%.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

A family of six (five new) thiophenyl bridged triarylamine-donor based dyes with pyridine anchoring groups have been synthesized and studied as sensitizers for the p-type dye-sensitized solar cell (p-DSSC). They comprise bis-dicyano acceptor systems with a single pyridyl binder incorporated directly into the triarylamine (1), or separated by a phenyl group (2); a mono-dicyano with two phenyl pyridine binders (3); and respective homologues 4 to 6 with pyridinium acceptors. In all cases, compared to their dicyano counterparts, the pyridinium based dyes have higher extinction coefficients and smaller HOMO-LUMO gaps that give broader spectrum absorption. Thus, despite lower dye uptake, devices based on pyridiniums 4 and 6 have identical power conversion efficiencies (eta) to the equivalent dicyano systems 1 and 3. However, the best performing device (eta = 0.06%) is based on the known bis-acceptor dicyano system 2, as the large size and double positive charge of 5 leads to a substantial disadvantage in loading on NiO. Absorbed-photon-to-current efficiencies for 5 are competitive with or higher than those of 2, implying a better per dye performance consistent with the absorption profile, and DFT calculations suggesting better charge separation. Thus, pyridiniums may provide a new, and easily accessible high performance acceptor for p-DSSC dyes, but are likely better paired with anionic binding groups such as carboxylates.

This paper reports on the synthesis, crystal structure and application of a novel hybrid bismuth-halide complex: (CN 2 SH 5 ) 3 BiI 6 (TBI) for supercapacitor applications, featuring merits including high areal capacitance, low cost, solution-processability and non-toxicity. Single crystal X-ray diffraction reveals that TBI crystallizes in the monoclinic system, with discrete [BiI 6 ] 3-octahedra as the inorganic motif. Utilizing TBI as the active supercapacitor electrode material with carbon cloth current collector and aqueous NaClO 4 electrolyte, an electrode areal capacitance of 3.32 F/cm 2 and a systemic specific capacitance of 1030 F/g was achieved when the device operates as an electric double-layer capacitor (EDLC). The supercapacitor device shows excellent capacitance retention even after 5,000 charge-discharge cycles. The powder XRD patterns, Raman spectroscopy and SEM images of TBI electrodes were compared before and after the cycling test to demonstrate the material stability and investigate the film morphology.

Supercapacitors are well-known as promising energy storage devices capable of bridging the gap between conventional electrolytic capacitors and batteries to deliver both high power and energy densities for applications in electric vehicles and a smart energy grid. However, many reported instances of high-capacitance pseudocapacitors employ strong Faradaic reactions that hinder fast charge-discharge cycles and long-term stability, limiting their commercial viability. In this study, we utilise an economical and solution-processable procedure to fabricate a Cs3Bi2I9-based symmetric supercapacitor employing both electric double layer capacitance and pseudocapacitance with an aqueous NaClO4 electrolyte to deliver an outstanding device areal capacitance of 2.4 F cm(-2) and specific capacitance of 280 F g(-1). The Cs3Bi2I9 device achieves an excellent 88% capacitance retention after 5000 charge-discharge cycles, proving its long-term cycle stability and promise as a practical supercapacitor. We characterise the time-dependent charge storage mechanisms through cyclic voltammetry and electrochemical impedance spectroscopy to find that electrostatic charge accumulation predominates at high potentials (0.3-0.6 V) whereas weak, Faradaic charge adsorption and pore penetration bolster charge storage at lower potentials (0.0-0.2 V).

Electrical double layer capacitors (EDLCs) featuring low-cost and solution-processable electrode materials have attracted significant research interest for their green and economical applications in energy harvesting and storage devices. Here, we demonstrate a novel synthetic route for films of an underexplored 3-D hexagonal bismuth chalcohalide, Bi13S18I2, and investigate its potential as the active electrode material in EDLC-type supercapacitors. The synthetic procedure has been optimised and comprises the lowest annealing temperature (150 C) and the shortest processing time (1 h) currently reported. When integrated in a symmetrical EDLC with an aqueous NaClO4 electrolyte, the Bi13S18I2-based device achieves a remarkable areal capacitance of 210.68 mF cm 2 with 99.7% capacitance retention after 5000 cycles. Both the Bi13S18I2 powder and thin-film electrodes have been characterized through XRD, XPS, Raman spectroscopy, and SEM. The superior stability, low-cost, and facile synthesis of Bi13S18I2 proves its promising potential for supercapacitor applications.

Dye-sensitized solar cells are photoelectrochemical devices, which are of great interest due to their ease of fabrication and attractive design.

We demonstrate a novel synthetic route to films of a bismuth chalcohalide, Bi13S18I2, and investigate its potential as the active electrode material in EDLC-type supercapacitors.

A novel hybrid visible-light photodetector was created using a planar p-type inorganic NiO layer in a junction with an organic electron acceptor layer. The effect of different oxygen pressures on formation of the NiO layer by pulsed laser deposition shows that higher pressure increases the charge carrier density of the film and lowers the dark current in the device. The addition of a monolayer of small molecules containing conjugated π systems and carboxyl groups at the device interface was also investigated and with correct alignment of the energy levels improves the device performance with respect to the quantum efficiency, responsivity, and photogeneration. The thickness of the organic layer was also optimized for the device, giving a responsivity of 1.54 × 10(-2) A W(-1) in 460 nm light.