Tuning Alkyl Chain Lengths of Oxasmaragdyrins-B(OR)₂ for Optimizing Hole-Transport and Efficiency in Perovskite Solar Cells

A major challenge toward commercialization of perovskite solar cells (PSCs) is the development of cost-effective hole-transport materials (HTMs) with good hole mobility and long-term stability. Porphyrinoids such as metal-free oxasmaragdyrins as alternative HTMs in PSCs show promising power conversion at lower costs. In this study, a difluoroboryl oxasmaragdyrin, SM09, has been modified by introducing alkoxy chains with different chain lengths (methoxy (OMe), ethoxy (OEt), butoxy (OBu), and octyloxy (OOct)) at the central core position, affecting molecular packing, varying intermolecular distances, and consequently altering the hole mobility. These modified oxasmaragdyrins were used as HTMs for the planar PSCs. The device performance was evaluated and correlated with the alkyl chain length and was rationalized by photophysical characterizations. The device efficiencies decrease with an increase in the alkyl chain length from the highest PCE of 15.47% for SM-OMe to 13.35% for SM-OOct. The best performance was obtained in SM-OMe, due to its higher hole mobility (3.75 × 10–4 cm2 V–1 s–1) and stronger p-type character. In the future, a simple tuning of alkyl chain length at central core positions of oxasmaragdyrin HTMs can be an effective strategy to enhance the power conversion efficiency (PCE) of PSCs

Tuning Alkyl Chain Lengths of Oxasmaragdyrins-B(OR)₂ for Optimizing Hole-Transport and Efficiency in Perovskite Solar Cells

A major challenge toward commercialization of perovskite solar cells (PSCs) is the development of cost-effective hole-transport materials (HTMs) with good hole mobility and long-term stability. Porphyrinoids such as metal-free oxasmaragdyrins as alternative HTMs in PSCs show promising power conversion at lower costs. In this study, a difluoroboryl oxasmaragdyrin, SM09, has been modified by introducing alkoxy chains with different chain lengths (methoxy (OMe), ethoxy (OEt), butoxy (OBu), and octyloxy (OOct)) at the central core position, affecting molecular packing, varying intermolecular distances, and consequently altering the hole mobility. These modified oxasmaragdyrins were used as HTMs for the planar PSCs. The device performance was evaluated and correlated with the alkyl chain length and was rationalized by photophysical characterizations. The device efficiencies decrease with an increase in the alkyl chain length from the highest PCE of 15.47% for SM-OMe to 13.35% for SM-OOct. The best performance was obtained in SM-OMe, due to its higher hole mobility (3.75 × 10–4 cm2 V–1 s–1) and stronger p-type character. In the future, a simple tuning of alkyl chain length at central core positions of oxasmaragdyrin HTMs can be an effective strategy to enhance the power conversion efficiency (PCE) of PSCs

Tuning Alkyl Chain Lengths of Oxasmaragdyrins-B(OR)₂ for Optimizing Hole-Transport and Efficiency in Perovskite Solar Cells

A major challenge toward commercialization of perovskite solar cells (PSCs) is the development of cost-effective hole-transport materials (HTMs) with good hole mobility and long-term stability. Porphyrinoids such as metal-free oxasmaragdyrins as alternative HTMs in PSCs show promising power conversion at lower costs. In this study, a difluoroboryl oxasmaragdyrin, SM09, has been modified by introducing alkoxy chains with different chain lengths (methoxy (OMe), ethoxy (OEt), butoxy (OBu), and octyloxy (OOct)) at the central core position, affecting molecular packing, varying intermolecular distances, and consequently altering the hole mobility. These modified oxasmaragdyrins were used as HTMs for the planar PSCs. The device performance was evaluated and correlated with the alkyl chain length and was rationalized by photophysical characterizations. The device efficiencies decrease with an increase in the alkyl chain length from the highest PCE of 15.47% for SM-OMe to 13.35% for SM-OOct. The best performance was obtained in SM-OMe, due to its higher hole mobility (3.75 × 10–4 cm2 V–1 s–1) and stronger p-type character. In the future, a simple tuning of alkyl chain length at central core positions of oxasmaragdyrin HTMs can be an effective strategy to enhance the power conversion efficiency (PCE) of PSCs

Tuning Alkyl Chain Lengths of Oxasmaragdyrins-B(OR)₂ for Optimizing Hole-Transport and Efficiency in Perovskite Solar Cells

A major challenge toward commercialization of perovskite solar cells (PSCs) is the development of cost-effective hole-transport materials (HTMs) with good hole mobility and long-term stability. Porphyrinoids such as metal-free oxasmaragdyrins as alternative HTMs in PSCs show promising power conversion at lower costs. In this study, a difluoroboryl oxasmaragdyrin, SM09, has been modified by introducing alkoxy chains with different chain lengths (methoxy (OMe), ethoxy (OEt), butoxy (OBu), and octyloxy (OOct)) at the central core position, affecting molecular packing, varying intermolecular distances, and consequently altering the hole mobility. These modified oxasmaragdyrins were used as HTMs for the planar PSCs. The device performance was evaluated and correlated with the alkyl chain length and was rationalized by photophysical characterizations. The device efficiencies decrease with an increase in the alkyl chain length from the highest PCE of 15.47% for SM-OMe to 13.35% for SM-OOct. The best performance was obtained in SM-OMe, due to its higher hole mobility (3.75 × 10–4 cm2 V–1 s–1) and stronger p-type character. In the future, a simple tuning of alkyl chain length at central core positions of oxasmaragdyrin HTMs can be an effective strategy to enhance the power conversion efficiency (PCE) of PSCs

Tuning Alkyl Chain Lengths of Oxasmaragdyrins-B(OR)₂ for Optimizing Hole-Transport and Efficiency in Perovskite Solar Cells

A major challenge toward commercialization of perovskite solar cells (PSCs) is the development of cost-effective hole-transport materials (HTMs) with good hole mobility and long-term stability. Porphyrinoids such as metal-free oxasmaragdyrins as alternative HTMs in PSCs show promising power conversion at lower costs. In this study, a difluoroboryl oxasmaragdyrin, SM09, has been modified by introducing alkoxy chains with different chain lengths (methoxy (OMe), ethoxy (OEt), butoxy (OBu), and octyloxy (OOct)) at the central core position, affecting molecular packing, varying intermolecular distances, and consequently altering the hole mobility. These modified oxasmaragdyrins were used as HTMs for the planar PSCs. The device performance was evaluated and correlated with the alkyl chain length and was rationalized by photophysical characterizations. The device efficiencies decrease with an increase in the alkyl chain length from the highest PCE of 15.47% for SM-OMe to 13.35% for SM-OOct. The best performance was obtained in SM-OMe, due to its higher hole mobility (3.75 × 10–4 cm2 V–1 s–1) and stronger p-type character. In the future, a simple tuning of alkyl chain length at central core positions of oxasmaragdyrin HTMs can be an effective strategy to enhance the power conversion efficiency (PCE) of PSCs

Electronic Structure Optimization of PdZn-Graphitic Carbon Nitride Nanocomposites as Electrocatalysts for Selective CO₂ to CO Conversion

Herein, a novel PdZn/g-C3N4 nanocomposite electrocatalyst, PdZnGCN, prepared from a facile hydrothermal reduction procedure for an efficient CO2 to CO conversion has been examined. This composite catalyst reduces CO2 at a thermodynamic overpotential of 0.79 V versus RHE with a 93.6% CO Faradaic efficiency and a CO partial current density of 4.4 mA cm–2. Moreover, the turnover frequency for PdZnGCN reaches 20 974 h–1 with an average selectivity of 95.4% for CO after 1 h and an energy efficiency approaching 59%, which is superior to most reported noble metals and metal alloys as electrocatalysts. The enhanced catalytic activity of this nanocomposite is due to synergistic interactions between PdZn and g-C3N4 as evidenced by optimum work function, zeta potential, CO desorption rate, and downshifted d-band center. Furthermore, suppressed grain growth during the formation of nanocomposites also results in faster reaction kinetics, as demonstrated by a lower Tafel slope (93.6 mV/dec) and a larger electrochemically active surface, consequently enhancing the overall performance

Development of Novel Mixed Halide/Superhalide Tin-Based Perovskites for Mesoscopic Carbon-Based Solar Cells

Tin perovskites suffer from poor stability and a self-doping effect. To solve this problem, we synthesized novel tin perovskites based on superhalide with varied ratios of tetrafluoroborate to iodide and implemented them into solar cells based on a mesoscopic carbon-electrode architecture because film formation was an issue in applying this material for a planar heterojunction device structure. We undertook quantum-chemical calculations based on plane-wave density functional theory (DFT) methods and explored the structural and electronic properties of tin perovskites FASnI3–x(BF4)x in the series x = 0, 1, 2, and 3. We found that only the x = 2 case, FASnI­(BF4)2, was successfully produced, beyond the standard FASnI3. The electrochemical impedance and X-ray photoelectron spectra indicate that the addition of tin tetrafluoroborate instead of SnI2 suppressed trap-assisted recombination by decreasing the Sn4+ content. The power conversion efficiency of the FASnI­(BF4)2 device with FAI and Sn­(BF4)2 in an equimolar ratio improved 72% relative to that of a standard FASnI3 solar cell, with satisfactory photostability under ambient air conditions