Understanding the energetics of electron transfer at the semiconductor interface is crucial for t... more Understanding the energetics of electron transfer at the semiconductor interface is crucial for the development of solar harvesting technologies, including photovoltaics, photocatalysis, and solar fuel systems.
The design of an efficient and highly selective organic polymeric semiconductor photocatalyst con... more The design of an efficient and highly selective organic polymeric semiconductor photocatalyst consisting of Earth‐abundant elements for solar fuel generation using seawater, and also deionized water, as a proton source is reported. The mesoporous g‐C3N4 synthesized using a conventional precursor (urea) shows significant H2 generation (ca. 33 000 μmol h−1 g−1) and drives the photoreduction of CO2 to CH4, along with trace amount of methanol. However, when the chosen precursor cyanamide is used, drastic improvement in H2 generation (ca. 41 600 μmol h−1 g−1) and CO2 photoreduction is observed. The introduction of a surface nitrogen deficiency and modification of the surface with Cu0 further enhances solar H2 generation (ca. 50 000 μmol h−1 g−1) and CO2 photoreduction (3.12 μmol h−1 g−1) activity, respectively, owing to improvement in light harvesting and charge separation, as revealed by a shorter average lifetime of 3.52 ns and higher Stern–Volmer quenching constant value of approximately 11.2 m−1. In addition, improved selectivity in CO2 photoreduction to only CH4 is also observed. The designed photocatalytic system is stable, with the solar H2 generation rate increasing even after 20 h under continuous illumination with a turnover number of 6500. When seawater used instead of deionized water, the overall solar fuel generation efficiencies of all photocatalysts marginally decreased owing to a decrease in the photogenerated charge‐carrier separation efficacy.
India has come up with many policies and programs to take action toward mitigation of carbon diox... more India has come up with many policies and programs to take action toward mitigation of carbon dioxide from the energy sector through rapid augmentation of renewable energy growth and energy efficiency improvement. However, there is also need to unify abatement and recycling measures like amplification of low-carbon technologies. Emissions from various industries can be captured and reused for the production of various value-added chemicals and fuels. This chapter briefly discusses all the chemical reactions which require carbon dioxide as a primary product, giving a brief detail of electrocatalytic and photocatalytic pathways in which the anthropogenic carbon dioxide can be activated and subsequently converted into value-added chemicals/fuels. Apart from that, certain issues related to scaling up the technology have been highlighted. The author concludes by putting light on various problems related to the technologies, which need efforts and research so as to achieve practically viable catalysts for CO2 conversion to chemicals and fuel.
There is ever‐growing interest to develop intrinsic white light emitting single‐phase phosphors t... more There is ever‐growing interest to develop intrinsic white light emitting single‐phase phosphors that have high CRI, devoid of bluish tinge, ease of synthesis and are scalable. Herein, manipulating vacuum pressure to instigate white light emission in Cu2+‐doped‐ZnS phosphors is reported. The detailed X‐ray diffraction and electron microscopy confirm the cubic phase of Cu2+‐doped‐ZnS phosphor having agglomerated particles (∼130–150 nm). The incorporation of Cu2+ in the ZnS lattice is substantiated by the anti‐Stokes shift of Raman peaks and shifting of XRD peaks to higher 2θ values. Upon increasing Cu2+ doping concentration, the resulted decrease in the FWHM of XRD peaks implies shrinkage of the ZnS lattice. Interestingly, by tailoring the excitation wavelength, the stoichiometry of dopant ion, and defect states by varying the vacuum pressure, the optimized ZSC‐3 (3% Cu2+‐doped‐ZnS) displays the origin of clear blue, green and red emission bands, consequently giving rise to white light emission (CIE values: 0.345:0398). The PLQY and average lifetime calculated for ZSC‐3 are 5.98% and 1.5 ms, respectively. Such intense white light emission prompted to fabricate a prototype using a 310 nm UV LED. It exhibits high CRI (97) and warm CCT (4538 K), meeting highly desired values for a white light‐emitting phosphor for different lighting and electroluminescence applications.
The development of robust systems for the conversion of solar energy into chemical fuels is an im... more The development of robust systems for the conversion of solar energy into chemical fuels is an important subject in renewable energy research. Key aspects are efficient and rapid catalysis of both fuel production (reduction of H2O or CO2), and water oxidation. Enzymes often have extraordinary and unique capabilities as electrocatalysts, and in this Perspective we consider the role that these molecules can play through their incorporation into model systems for solar fuel production, or as inspiration for synthetic catalysts.
The chemically coupled MOS2 with nitrogen deficient 2-D triazine polymeric m-C3Nx photocatalyst d... more The chemically coupled MOS2 with nitrogen deficient 2-D triazine polymeric m-C3Nx photocatalyst drives the selective and efficient photocatalytic reduction of CO2 to CO (FE: 31%), – three folds higher than that of MoS2 decorated mpg-C3N4.
Understanding the energetics of electron transfer at the semiconductor interface is crucial for t... more Understanding the energetics of electron transfer at the semiconductor interface is crucial for the development of solar harvesting technologies, including photovoltaics, photocatalysis, and solar fuel systems.
The design of an efficient and highly selective organic polymeric semiconductor photocatalyst con... more The design of an efficient and highly selective organic polymeric semiconductor photocatalyst consisting of Earth‐abundant elements for solar fuel generation using seawater, and also deionized water, as a proton source is reported. The mesoporous g‐C3N4 synthesized using a conventional precursor (urea) shows significant H2 generation (ca. 33 000 μmol h−1 g−1) and drives the photoreduction of CO2 to CH4, along with trace amount of methanol. However, when the chosen precursor cyanamide is used, drastic improvement in H2 generation (ca. 41 600 μmol h−1 g−1) and CO2 photoreduction is observed. The introduction of a surface nitrogen deficiency and modification of the surface with Cu0 further enhances solar H2 generation (ca. 50 000 μmol h−1 g−1) and CO2 photoreduction (3.12 μmol h−1 g−1) activity, respectively, owing to improvement in light harvesting and charge separation, as revealed by a shorter average lifetime of 3.52 ns and higher Stern–Volmer quenching constant value of approximately 11.2 m−1. In addition, improved selectivity in CO2 photoreduction to only CH4 is also observed. The designed photocatalytic system is stable, with the solar H2 generation rate increasing even after 20 h under continuous illumination with a turnover number of 6500. When seawater used instead of deionized water, the overall solar fuel generation efficiencies of all photocatalysts marginally decreased owing to a decrease in the photogenerated charge‐carrier separation efficacy.
India has come up with many policies and programs to take action toward mitigation of carbon diox... more India has come up with many policies and programs to take action toward mitigation of carbon dioxide from the energy sector through rapid augmentation of renewable energy growth and energy efficiency improvement. However, there is also need to unify abatement and recycling measures like amplification of low-carbon technologies. Emissions from various industries can be captured and reused for the production of various value-added chemicals and fuels. This chapter briefly discusses all the chemical reactions which require carbon dioxide as a primary product, giving a brief detail of electrocatalytic and photocatalytic pathways in which the anthropogenic carbon dioxide can be activated and subsequently converted into value-added chemicals/fuels. Apart from that, certain issues related to scaling up the technology have been highlighted. The author concludes by putting light on various problems related to the technologies, which need efforts and research so as to achieve practically viable catalysts for CO2 conversion to chemicals and fuel.
There is ever‐growing interest to develop intrinsic white light emitting single‐phase phosphors t... more There is ever‐growing interest to develop intrinsic white light emitting single‐phase phosphors that have high CRI, devoid of bluish tinge, ease of synthesis and are scalable. Herein, manipulating vacuum pressure to instigate white light emission in Cu2+‐doped‐ZnS phosphors is reported. The detailed X‐ray diffraction and electron microscopy confirm the cubic phase of Cu2+‐doped‐ZnS phosphor having agglomerated particles (∼130–150 nm). The incorporation of Cu2+ in the ZnS lattice is substantiated by the anti‐Stokes shift of Raman peaks and shifting of XRD peaks to higher 2θ values. Upon increasing Cu2+ doping concentration, the resulted decrease in the FWHM of XRD peaks implies shrinkage of the ZnS lattice. Interestingly, by tailoring the excitation wavelength, the stoichiometry of dopant ion, and defect states by varying the vacuum pressure, the optimized ZSC‐3 (3% Cu2+‐doped‐ZnS) displays the origin of clear blue, green and red emission bands, consequently giving rise to white light emission (CIE values: 0.345:0398). The PLQY and average lifetime calculated for ZSC‐3 are 5.98% and 1.5 ms, respectively. Such intense white light emission prompted to fabricate a prototype using a 310 nm UV LED. It exhibits high CRI (97) and warm CCT (4538 K), meeting highly desired values for a white light‐emitting phosphor for different lighting and electroluminescence applications.
The development of robust systems for the conversion of solar energy into chemical fuels is an im... more The development of robust systems for the conversion of solar energy into chemical fuels is an important subject in renewable energy research. Key aspects are efficient and rapid catalysis of both fuel production (reduction of H2O or CO2), and water oxidation. Enzymes often have extraordinary and unique capabilities as electrocatalysts, and in this Perspective we consider the role that these molecules can play through their incorporation into model systems for solar fuel production, or as inspiration for synthetic catalysts.
The chemically coupled MOS2 with nitrogen deficient 2-D triazine polymeric m-C3Nx photocatalyst d... more The chemically coupled MOS2 with nitrogen deficient 2-D triazine polymeric m-C3Nx photocatalyst drives the selective and efficient photocatalytic reduction of CO2 to CO (FE: 31%), – three folds higher than that of MoS2 decorated mpg-C3N4.
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