This modern reference explains photon upconversion technology using nanoparticles from first principles to novel and future applications in imaging, sensing, catalysis, energy technology, biomedicine, and many other areas. Expert authors discuss both established and novel materials and applications, going far beyond the coverage of previously published books on the subject. Key topics covered in the book include: - Synthesis, characterization, and basic properties of nanoparticles with photon-upconverting properties - New types of upconverting nanoparticles, including transition metal- and rare earth-doped materials, metal-organic frameworks, core/shell particles, and surface-modified particles - Current and emerging application areas for upconverting nanoparticles, including heating, lighting, sensing, and detection - Biomedical uses of nanoparticles, including photodynamic therapy
Photon upconversion using nanoparticles has opened the door to a new universe of light-powered technology. This book is a key resource for scientists, physicists, and chemists across a wide range of disciplines who wish to master the theory, methods and applications of this powerful new technology.
Table of Contents
Preface xv
1 Introduction to Upconversion and Upconverting Nanoparticles 1
Manisha Mondal and Vineet Kumar Rai
1.1 Introduction 1
1.2 Frequency Conversion and Its Various Processes 2
1.2.1 Stokes Emission 2
1.2.2 Anti-Stokes Emission 2
1.2.2.1 Ground/Excited-State Absorption (GSA/ESA) 3
1.2.2.2 Energy Transfer Upconversion (ETU) 4
1.2.2.3 Cooperative Luminescence and Cooperative Sensitization Upconversion (csu) 5
1.2.2.4 Cross-relaxation (CR) and Photon Avalanche (PA) 6
1.3 Transition Metals and Their Properties 7
1.4 Rare Earths and Their Properties 8
1.4.1 Trivalent Rare-Earth Ions 9
1.4.1.1 Electronic Structure 9
1.4.1.2 Interaction of Rare-Earth Ions 10
1.4.1.3 Dieke Diagram 13
1.4.2 Divalent Rare-Earth Ions 13
1.5 Excitation and De-excitation Processes of Rare Earths in Solid Materials 15
1.5.1 Excitation Processes 15
1.5.1.1 f-f Transition 15
1.5.1.2 f-d Transition 15
1.5.1.3 Charge Transfer Transition 15
1.5.2 Emission Processes 15
1.5.2.1 Emission via Radiative Transitions 15
1.5.2.2 Emission via Nonradiative Transitions 16
1.5.2.3 Energy Transfer Processes 16
1.6 Rate Equations Relevant to UC Mechanism 18
1.6.1 Rate Equations in a Basic Three-Level System 18
1.6.2 Rate Equation Related to Pump Power-Dependent UC Emission 19
1.7 Theoretical Description of Optical Characteristics of Rare-Earth Ions 20
1.7.1 Judd-Ofelt (J-O) Theory and Calculation of Radiative Parameters 21
1.7.2 Nephelauxetic Effect 22
1.8 An Introduction to Upconverting Nanoparticles 22
Acknowledgments 23
References 23
2 Synthesis Protocol of Upconversion Nanoparticles 31
Lakshmi Mukhopadhyay and Vineet Kumar Rai
2.1 Introduction 31
2.2 Host Matrix 32
2.3 Synthetic Strategy of UC Nanomaterials 33
2.3.1 Solid-State Reaction Technique 34
2.3.2 Coprecipitation Technique 35
2.3.3 Sol-Gel Technique 36
2.3.4 Hydro(solvo)thermal Technique 39
2.3.5 Combustion Technique 40
2.3.6 Thermolysis Technique 42
2.3.6.1 Thermolysis in OA-Based Mixed Solvents 43
2.3.6.2 Thermolysis in OM-Based Mixed Solvents 43
2.3.6.3 Thermolysis in TOPO-Based Mixed Solvents 43
2.3.7 Microwave-Assisted Synthesis Technique 44
2.4 Synthesis Techniques for Fabricating Core@shell Architectures 45
2.4.1 Solid-Phase Reaction 45
2.4.2 Liquid-Phase Reaction 46
2.4.2.1 Stöber Technique 46
2.4.2.2 Microemulsion Technique 48
2.4.3 Gas-Phase Reaction 51
2.4.4 Mechanical Mixing 52
2.5 Other Synthesis Strategies to Develop Lanthanide-Doped UCNPs 52
2.6 Conclusion 53
References 53
3 Characterization Techniques and Analysis 67
Neha Jain, Prince K. Jain, Rajan K. Singh, Amit Srivastava, and Jai Singh
3.1 Introduction 67
3.2 X-Ray Diffraction (XRD) 69
3.3 X-ray Photoelectron Spectroscopy (XPS) 72
3.4 Field Emission Scanning Electron Microscopy (FESEM) 74
3.5 Transmission Electron Microscopy (TEM) 76
3.6 Energy-Dispersive X-ray Spectroscopy (EDS) 79
3.7 Thermogravimetric Analysis (TGA) 81
3.8 Ultraviolet-Visible-Near-Infrared (UV-Vis-NIR) Absorption Spectroscopy 82
3.9 Dynamic Light Scattering (DLS) 84
3.10 Photoluminescence (PL) Study 85
3.11 Pump Power-Dependent UC 87
3.12 Recognition of Emission Color and Colorimetric Theory 88
Acknowledgment 89
References 89
4 Raman and FTIR Spectroscopic Techniques and Their Applications 97
Saurav K. Ojha and Animesh K. Ojha
4.1 Raman Spectroscopy 97
4.2 Fourier Transform Infrared (FTIR) Spectroscopy 99
4.2.1 FTIR in Transmission Mode 100
4.2.2 Attenuated Total Reflectance (ATR) 100
4.2.3 Diffuse Reflectance Infrared Fourier Transform Spectroscopy (drifts) 100
4.3 Applications of Raman Spectroscopy 100
4.3.1 Raman Study of Molecular Association in Hydrogen-Bonded Systems 100
4.3.2 Surface-Enhanced Raman Spectroscopy (SERS) 104
4.3.3 Resonance Raman Spectroscopy (RRS) 106
4.3.4 Raman Spectroscopy of Semiconducting, Superconducting, and Perovskite Materials 107
4.4 Applications of FTIR Spectroscopy 108
4.4.1 FTIR Spectroscopy of Semiconductor, Superconductor, Hazardous, and Perovskite Materials 108
4.5 Raman and FTIR Spectroscopy of Upconverting Nanoparticles 109
References 110
5 Fundamental Aspects of Upconverting Nanoparticles (UCNPs) Based on Their Properties 117
Sushil K. Ranjan, Sasank Pattnaik, Vishab Kesarwani, and Vineet Kumar Rai
5.1 Introduction 117
5.2 Elucidation of Dynamics of UCNPs on the Basis of Fluorescence Decay Times 120
5.2.1 General Understanding of Depopulation Processes and UC Decay 120
5.2.2 Differentiating the ESA and ETU Mechanism Based on the Decay Profile 121
5.2.3 Theoretical and Experimental Approach of Understanding the Factors Affecting Upconversion Decay 123
5.3 Measurement of Quantum Yield of UCNPs 131
5.3.1 Role of Quantum Yield in Upconversion 132
5.3.2 Optical Methods of Measuring Quantum Yield of Upconverting Nanoparticles (UCNPs) 133
5.3.2.1 Relative Method of Measuring Quantum Yield 133
5.3.2.2 Absolute Method of Measuring Quantum Yield 133
5.3.2.3 Measurement of Intrinsic Quantum Yield of Lanthanide-Based Materials Using Lifetimes 134
5.3.3 Some Other Methods of Determining Quantum Yield 134
5.3.3.1 Photo-acoustic Spectroscopy (PAS) 134
5.3.3.2 Thermal Lensing (TL) Method 135
References 135
6 Frequency Upconversion in UCNPs Containing Transition Metal Ions 141
Manisha Prasad and Vineet Kumar Rai
6.1 Introduction 141
6.2 Synthesis of Transition Metal Ion-Activated Luminescent Nanomaterials 143
6.3 Structural and Optical Characterizations 143
6.4 Frequency Upconversion and Its Various Mechanisms 144
6.5 Applications 144
6.6 Mechanism of Transition Metal Ions in Crystal Field 145
6.6.1 UC Mechanisms in Mn-Based System 146
6.6.2 UC Mechanisms in Mn 4+ - and Ti 2+ -Based Systems 151
6.6.3 UC Mechanisms in Cr 3+ -Based System 153
6.6.4 UC Mechanisms in the Fe 3+ -Based System 155
6.6.5 UC Mechanisms in Co 3+ - and Ni 2+ -Based System 157
6.6.6 UC Mechanisms in Cu 2+ -, Zn 2+ -, and Zr 4+ -Based System 158
6.6.7 UC Mechanisms in Nb 5+ -, Mo 3+ -, Ru-, and Ag + -Based System 160
6.6.8 UC Mechanisms in W 6+ - and Re 4+ -Based System 161
6.6.9 UC Mechanisms in Os 4+ - and Au-Based System 162
References 164
7 Frequency Upconversion in UCNPs Containing Rare-Earth Ions 171
Sasank Pattnaik and Vineet Kumar Rai
7.1 Introduction 171
7.2 Familiarization with the Spectroscopic Behavior of RE 3+ Ion-Doped UCNPs 173
7.2.1 Physics of Trivalent Rare-Earth Ions 173
7.2.1.1 UC Mechanisms in Yb 3+ - and Pr 3+ -Based Systems 174
7.2.1.2 UC Mechanisms in Er-Based Systems 175
7.2.1.3 UC Mechanisms in Ho-Based Systems 177
7.2.1.4 UC Mechanisms in Tm-Based Systems 179
7.2.1.5 UC Mechanisms in Nd-Based Systems 181
7.2.1.6 Tri-Doped Systems 181
7.2.2 Color Modulation in UCNPs 184
7.2.2.1 Role of Dopant Concentration and Combination of RE 3+ Ions in Color Modulation 184
7.2.2.2 Role of Host/Dopant Combination in Color Modulation 186
7.2.2.3 Controlling the Emission Color Through Phonon Effects 186
7.2.2.4 Tuning UC Emission Using FRET 188
7.2.3 Quenching Mechanisms in UCNPs 190
7.3 Routes to Enhance Upconversion Luminescence in Nanoparticles 190
7.3.1 Dye Sensitization Techniques 191
7.3.2 Concentration Quenching Minimization 192
7.3.2.1 Suppression of Surface-Related Quenching 192
7.3.2.2 Removal of Detrimental Cross-Relaxation 193
7.3.3 Confinement of Energy Migration 194
7.3.4 Other Techniques to Enhance Upconversion Emission 195
7.3.4.1 Crystal-Phase Modification 195
7.3.4.2 Constructing an Active Core/Active Shell Strategy 195
7.3.4.3 Conjugating Surface Plasmon Resonance Technique 195
7.3.4.4 Dielectric Superlensing-Mediated Strategy 196
7.4 Technological Applications 197
7.4.1 Photonic Applications 197
7.4.1.1 Light-Emitting Diodes (LEDs) 197
7.4.1.2 Photovoltaic Applications 198
7.4.2 Bioimaging 199
7.4.3 Photo-Induced Therapeutic Applications 200
7.4.3.1 Photodynamic Therapy 201
7.4.3.2 Photothermal Therapy 201
7.4.3.3 Photoactivated Chemotherapy (PACT) 202
7.4.4 Other Emerging Applications 203
7.4.4.1 Anticounterfeiting 203
7.4.4.2 Sensing and Detection 203
7.4.4.3 Optogenetic Stimulation 205
7.4.4.4 NIR Image Vision of Mammals 205
References 206
8 Smart Upconverting Nanoparticles and New Types of Upconverting Nanoparticles 221
Akhilesh K. Singh
8.1 Introduction 221
8.2 Upconverting Core-Shell Nanostructures 222
8.3 Hybrid Upconverting Nanoparticles 224
8.4 Magnetic Upconverting Nanoparticles 226
8.5 UC-Based Metal-Organic Frameworks 228
8.6 Smart UCNPs for Security Applications 230
8.7 Smart Upconverting Nanoparticles for Biological Applications 233
8.8 Smart Upconverting Nanoparticles for Sensing 235
8.9 Conclusion 236
References 237
9 Surface Modification and (Bio)Functionalization of Upconverting Nanoparticles 241
Yashashchandra Dwivedi
9.1 Introduction 241
9.2 Upconverting Nanomaterials 242
9.3 Surface Modification 245
9.4 Biofunctionalization of Upconverting Materials and Applications 247
References 257
10 Frequency Upconversion in Core@shell Nanoparticles 267
Raghumani S. Ningthoujam, Rashmi Joshi, and Manas Srivastava
10.1 Introduction 267
10.1.1 Downconversion 267
10.1.2 Upconversion 271
10.2 Synthesis of Core@shell and Core@shell@shell UCNPs 272
10.2.1 Thermolysis Method 272
10.2.2 Hot Injection 276
10.2.3 Cation Exchange 277
10.2.4 Structural Characterizations 277
10.2.5 Optical Characterization 281
10.2.5.1 Normal Conversion Process in Ln-Doped Core@shell Nanoparticles 283
10.2.5.2 Loop-Type and Avalanche-Type Upconversion Processes in Core@shell Nanoparticles 289
10.3 Frequency Upconversion and Its Various Mechanisms 291
10.3.1 Inorganic-Based Upconversion 291
10.4 Applications 297
10.4.1 Bioimaging Applications 297
10.4.1.1 Luminescence-Based Imaging 297
10.4.1.2 Other Imaging Probes (MRI, CT, and SPECT) 299
10.4.2 Photothermal Therapy (PTT) 301
10.4.3 Photodynamic Therapy (PDT) 303
10.4.4 Temperature Sensor 306
10.4.5 Security Ink 308
10.5 Conclusion 310
Acknowledgment 311
References 311
11 UCNPs in Solar, Forensic, Security Ink, and Anti-counterfeiting Applications 319
Kaushal Kumar, Neeraj Kumar Mishra, and Kumar Shwetabh
11.1 Introduction 319
11.2 UCNPs for Solar Cells 320
11.2.1 C-Si Solar Cells 321
11.2.2 Amorphous Silicon Solar Cells 323
11.2.3 GaAs-Based Solar Cells 324
11.2.4 Dye-Sensitized Solar Cells (DSSCs) 324
11.3 Forensic, Security Printing, and Anti-counterfeiting Applications 325
11.4 Biomedicals 331
11.4.1 Bioimaging 333
11.4.2 Biosensing 336
11.5 Display and Lighting Purposes 339
References 340
12 Application of Upconversion in Photocatalysis and Photodetectors 347
Priyam Singh, Sachin Singh, and Prabhakar Singh Sunil Kumar Singh
12.1 Introduction 347
12.2 Photocatalysis 349
12.3 Photodetector 357
12.4 Conclusion 365
References 365
13 UCNPs in Lighting and Displays 375
Riya Dey
13.1 Introduction 375
13.2 Major Factors that Affect the UC Emission Efficiency 375
13.3 UC Mechanisms with Rate Equations 378
13.3.1 Pump Power Dependence in the Case of Dominant ETU-Assisted Upconversion over ESA 379
13.3.2 Pump Power Dependence in the Case of Dominant ESA-Assisted Upconversion over ETU 380
13.4 UCNPs in Solid-State Laser 380
13.5 UCNPs in Solid-State Lighting and Displays 384
13.5.1 Requirements for LED Applications 384
References 388
14 Upconversion Nanoparticles in pH Sensing Applications 395
Manoj Kumar Mahata, Ranjit De, and Kang Taek Lee
14.1 Introduction 395
14.2 Basic Properties of UCNPs 397
14.3 Working Principle of UCNP-Based pH Sensor 400
14.4 Photon Upconversion-Based pH Sensing Systems 401
14.4.1 Upconversion Nanoparticles as pH Sensors 401
14.4.2 Upconversion-Based pH Sensing Membranes 405
14.5 Conclusion 410
References 411
15 Upconversion Nanoparticles in Temperature Sensing and Optical Heating Applications 417
Praveen K. Shahi and Shyam B. Rai
15.1 Introduction 417
15.2 Classification of Temperature Sensors: Primary and Secondary Thermometers 420
15.3 Performance of Temperature Sensors 420
15.3.1 Thermal Sensitivity 421
15.3.2 Thermal Uncertainty (δT) 421
15.3.3 Reproducibility and Repeatability 422
15.4 Temperature Sensing with Luminescence 423
15.4.1 Time-Integrated Schemes 424
15.4.1.1 Fluorescence Intensity Ratio (FIR) or Band Shape 424
15.4.1.2 Bandwidth 426
15.4.2 Lifetime Technique 427
15.5 Upconversion (UC) and UC-Based Thermal Sensor of Ln 3+ Ions 427
15.5.1 Upconversion (UC) and Upconverting Nanoparticles (UCNPs) 427
15.5.2 Single-Center UC Nanothermometers and Multicenter UC Nanothermometers 428
15.5.3 Complex Systems 430
15.6 Optical Heating 433
References 437
16 Upconverting Nanoparticles in Pollutant Degradation and Hydrogen Generation 449
Wanni Wang, Zhaoyou Chu, Benjin Chen, and Haisheng Qian
16.1 Introduction 449
16.2 Degradation of Organic Pollutants 450
16.2.1 Degradation of RhB 451
16.2.2 Degradation of MB 455
16.2.3 Degradation of MO 460
16.2.4 Degradation of Various Organic Pollutants 462
16.2.5 Others 467
16.3 Degradation of Inorganic Pollutants 469
16.4 Photocatalytic Hydrogen Production 473
16.5 Conclusion 481
References 481
17 Upconverting Nanoparticles in the Detection of Fungicides and Plant Viruses 493
Vishab Kesarwani and Vineet Kumar Rai
17.1 Introduction 493
17.2 Visual Detection of Fungicides 495
17.2.1 Detection Mechanisms 495
17.2.1.1 Forster Resonance Energy Transfer (FRET) 495
17.2.1.2 Inner Filter Effect (IFE) 496
17.2.1.3 Photoinduced Electron Transfer (PET) 499
17.2.1.4 Electron Exchange (EE) 500
17.2.2 Significant Works on Upconversion-Based Fungicide Detection 500
17.3 Detection of Plant Viruses 505
17.3.1 Plant Virus Detection/Management Strategies 505
17.3.1.1 Direct Interactions 505
17.3.1.2 Indirect Interactions 505
17.3.1.3 NPs as Biosensors for Virus Detection 507
17.3.1.4 RNAi Process for Antiviral Protection 507
17.3.2 Significant Works on Plant Virus Detection Based on UCNPs 507
17.4 Future Challenges Regarding NP-Based Fungicide and Plant Virus Detection 509
References 510
18 Upconversion Nanoparticles in Biological Applications 517
Poulami Mukherjee and Sumanta Kumar Sahu
18.1 Introduction 517
18.2 Upconversion Nanoparticles in Bioimaging 518
18.2.1 Cell Imaging 518
18.2.2 Multimodal Imaging 520
18.3 Upconversion Nanoparticles in Drug Delivery 522
18.3.1 Different Types of Surface Modification 524
18.3.1.1 Polymer Coating 524
18.3.1.2 Silica Coating 524
18.3.1.3 Metal Oxide-Coated UCNPs 525
18.3.1.4 Functionalization of UCNPs 525
18.3.1.5 Metal-Organic Framework Coating 525
18.3.2 Drug Release 526
18.3.2.1 NIR-Triggered Drug Delivery System 526
18.3.2.2 pH and Thermoresponsive Drug Release 526
18.4 Upconversion in Photodynamic Therapy 526
18.4.1 Surface Modification of UCNPs for PDT 529
18.5 Photothermal Therapy 531
References 533
Index 539
