Photocatalytic Water Splitting and Carbon Dioxide Reduction

Hammer, Nathan I.; Sutton, Sarah; Delcamp, Jared H.; Graham, J.

doi:10.1007/978-1-4614-6431-0_46-2

Cited by 5 publications

(40 citation statements)

References 111 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The remaining Re-ligand bonds change a relatively minor amount with the Re-CO and Re-N bonds slightly shortening and the Re-NHC bond slightly increasing in length by ≤0.03 Å. This suggests that the irreversible event occurring upon the first reduction of Re(pyNHC-PhCF 3 )(CO) 3 Br is the loss of Br. The increased lability of this halide is potentially affected by the electron-rich nature of the NHC ring both increasing electron density at the Re center and weakly (relative to a pyridyl) stabilizing the ligand centered anion of the reduced complex.…”

Section: Computational Analysis: Role Of the Ph-cf3 Substituentmentioning

confidence: 83%

“…The Re-Br bond was found to substantially lengthen upon reduction by 0.08 Å when the neutral catalyst is compared with the singly reduced catalyst. The remaining Re-ligand The computational results also aid in understanding the unique irreversibility of the NHC catalysts toward single-electron reduction when compared with the reversible first reduction of Re(bpy)(CO) 3 Br [10]. The Re-Br bond was found to substantially lengthen upon reduction by 0.08 Å when the neutral catalyst is compared with the singly reduced catalyst.…”

Section: Computational Analysis: Role Of the Ph-cf3 Substituentmentioning

confidence: 99%

“…Despite more than 30 years of exploration, very few catalysts meet these criteria with a single metal center, and nearly all of them are based on one of five frameworks: Fe-p-TMA, Ir(tpy)(ppy)X, Ir(tpy)(bpy)X, Re(bpy)(CO) 3 X, or Re(pyNHC-R)(CO) 3 X (Figure 1) [7][8][9][10][11][12]. Among these catalysts, the Re(pyNHC-R)(CO) 3 X catalyst is unique in allowing the reduction of CO 2 to occur at the first reduction potential of the neutral catalyst ( Figure 2) [10,13]. Typically, CO 2 reduction photocatalysts first undergo photoexcitation followed by electron transfer from a sacrificial electron donor (SED) to give the anionic catalyst (Figure 2a).…”

Section: Introductionmentioning

confidence: 99%

“…Here, we reasoned that this group allows better delocalization of the added electron on the singly reduced catalyst across the ligand framework since the lowest energy excitation is thought to be a metal-to-ligand charge transfer (MLCT) followed by addition of an electron [25][26][27]. To analyze the role of the phenyl-CF 3 substituent, the geometry of Re(pyNHC-PhCF 3 )(CO) 3 Br was first optimized with DFT at the M06-L/6-31++G(d,p) level. Analysis of the highest occupied molecular orbital (HOMO) distribution shows the orbital primarily situated on the Re-metal center, the CO ligands, and the Br ligand with no contribution from the pyNHC-PhCF 3 ligand (Figure 3).…”

Section: Introductionmentioning

confidence: 99%

“…Generic catalytic cycles for catalysts that reduce CO 2 after (a) the second catalyst reduction event, such as benchmark bpy-based Re(bpy)(CO) 3 Br, or (b) the first catalyst reduction event, such as NHC-based Re(pyNHC-PhCF 3 )(CO) 3 Br. The second SED electron transfer likely occurs after CO loss.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

A Robust Pyridyl-NHC-Ligated Rhenium Photocatalyst for CO2 Reduction in the Presence of Water and Oxygen

et al. 2018

Self Cite

View full text Add to dashboard Cite

Re(pyNHC-PhCF 3 )(CO) 3 Br is a highly active photocatalyst for CO 2 reduction. The PhCF 3 derivative was previously empirically shown to be a robust catalyst. Here, the role of the PhCF 3 group is probed computationally and the robust nature of this catalyst is analyzed with regard to the presence of water and oxygen introduced in controlled amounts during the photocatalytic reduction of CO 2 to CO with visible light. This complex was found to work well from 0-1% water concentration reproducibly; however, trace amounts of water were required for benchmark Re(bpy)(CO) 3 Cl to give reproducible reactivity. When ambient air is added to the reaction mixture, the NHC complex was found to retain substantial performance (~50% of optimized reactivity) at up to 40% ambient atmosphere and 60% CO 2 while the Re(bpy)(CO) 3 Cl complex was found to give a dramatically reduced CO 2 reduction reactivity upon introduction of ambient atmosphere. Through the use of time-correlated single photon counting studies and prior electrochemical results, we reasoned that this enhanced catalyst resilience is due to a mechanistic difference between the NHC-and bpy-based catalysts. These results highlight an important feature of this NHC-ligated catalyst: substantially enhanced stability toward common reaction contaminates.

show abstract

Section: Computational Analysis: Role Of the Ph-cf3 Substituentmentioning

confidence: 83%

Section: Computational Analysis: Role Of the Ph-cf3 Substituentmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

A Robust Pyridyl-NHC-Ligated Rhenium Photocatalyst for CO2 Reduction in the Presence of Water and Oxygen

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

The Role of Antireflective Coating CYTOP, Immersion Oil, and Sensitizer Selection in Fabricating a 2.3 V, 10% Power Conversion Efficiency SSM‐DSC Device

Cheema

Delcamp

2019

Advanced Energy Materials

View full text Add to dashboard Cite

for maximizing power output from an illuminated area is through the use of multijunction solar cell constructs. [3] Recently, we put forward the first sequential series multijunction dye-sensitized solar cell (SSM-DSC), which could power solarto-fuel conversion directly from a single illuminated area. [4] This construct showed solar-to-fuel conversion efficiencies of up to 3% for CO 2 to CO and H 2 O to H 2 and O 2 reactions in the seminal report of a purely DSC-based technology powering these processes from a single illuminated area device without bias. [4b] The use of a DSC system to power these solar-to-fuel conversion processes is attractive due to the processability, stability, and already relatively high photovoltage outputs from DSC devices. [4a] The SSM-DSC construct capitalizes on the high photovoltages of traditional DSC devices in dividing photons according to potential energy to generate high voltage outputs through a summation of subcell photovoltages. SSM-DSC devices are simple to construct with a direct stacking of subcells sequentially wired in series. In this configuration, devices can be optimized individually in terms of TiO 2 thickness and sensitizer choice to achieve well-matched photocurrents for higher performing SSM-DSC devices since current is limited by the lowest current device in the series. However, within this design, significant light losses exist between each subcell, especially at the glass-air interface where diffraction and reflection are the highest due to significantly mismatched refractive indexes of glass (n = 1.52) and air (n = 1) (Figure 1). To minimize these losses, we put forward the use of a simple-to-apply antireflective coating in the form of CYTOP along with an immersion oil with a similar refractive index to glass between each subcell (Figure 2).CYTOP is known in the field of optoelectronics with recent uses as a gate dielectric, a support layer within devices, as a selfcleaning surface, a solution substrate patterning material, and as an insulating tunneling layer within devices. [5] No reports were apparent from our searches for the specific use of CYTOP as an antireflective coating with organic or dye-sensitized solar cells. The use of CYTOP and immersion oil as optical interfacial loss diminishing components allows for an increase of photon flux throughout the SSM-DSC system to boost photocurrent values for a more overall efficient system. Sequential series multijunction dye-sensitized solar cells (SSM-DSCs) canpower solar-to-fuel processes with a single illuminated area device. Dye selection and strategies limiting photon losses are critical in SSM-DSC devices for higher performance systems. Herein, an efficient and readily applicable spin coating protocol on glass surfaces with an antireflective fluoropolymer (CYTOP) is applied to an SSM-DSC architecture. Combining CYTOP with the use of an immersion oil between glass spacers in a three subcell SSM-DSC with judiciously selected TiO 2 photoanode sensitizers and thicknesses, an overall power conversion efficie...

show abstract

Polymers without Petrochemicals: Sustainable Routes to Conventional Monomers

et al. 2022

View full text Add to dashboard Cite

Access to a wide range of plastic materials has been rationalized by the increased demand from growing populations and the development of high-throughput production systems. Plastic materials at low costs with reliable properties have been utilized in many everyday products. Multibillion-dollar companies are established around these plastic materials, and each polymer takes years to optimize, secure intellectual property, comply with the regulatory bodies such as the Registration, Evaluation, Authorisation and Restriction of Chemicals and the Environmental Protection Agency and develop consumer confidence. Therefore, developing a fully sustainable new plastic material with even a slightly different chemical structure is a costly and long process. Hence, the production of the common plastic materials with exactly the same chemical structures that does not require any new registration processes better reflects the reality of how to address the critical future of sustainable plastics. In this review, we have highlighted the very recent examples on the synthesis of common monomers using chemicals from sustainable feedstocks that can be used as a like-for-like substitute to prepare conventional petrochemical-free thermoplastics.

show abstract

Photocatalytic Water Splitting and Carbon Dioxide Reduction

Cited by 5 publications

References 111 publications

A Robust Pyridyl-NHC-Ligated Rhenium Photocatalyst for CO2 Reduction in the Presence of Water and Oxygen

A Robust Pyridyl-NHC-Ligated Rhenium Photocatalyst for CO2 Reduction in the Presence of Water and Oxygen

The Role of Antireflective Coating CYTOP, Immersion Oil, and Sensitizer Selection in Fabricating a 2.3 V, 10% Power Conversion Efficiency SSM‐DSC Device

Polymers without Petrochemicals: Sustainable Routes to Conventional Monomers

Contact Info

Product

Resources

About