Current Development in Lead-Free <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.524699pt" id="M1" height="16.2494pt" version="1.1" viewBox="-0.0657574 -11.7247 31.7305 16.2494" width="31.7305pt"><g transform="matrix(.018,0,0,-0.018,0,0)"><path id="g190-67" d="M372 352C427 368 507 407 507 502C507 548 486 592 451 616C420 638 376 650 301 650H44V622C124 616 128 610 128 527V123C128 40 122 34 36 28V0H257C336 0 402 12 453 40C512 72 548 124 548 191C548 291 471 335 372 350V352ZM213 362V558C213 591 216 602 226 608C235 614 258 618 282 618C377 618 415 558 415 490C415 406 369 362 260 362H213ZM213 328H258C380 328 450 283 450 181C450 76 377 35 296 34C231 34 213 53 213 125V328Z"/></g><g transform="matrix(.018,0,0,-0.018,10.373,0)"><path id="g190-106" d="M135 536C164 536 186 560 186 587C186 617 164 639 136 639C109 639 85 617 85 587C85 560 109 536 135 536ZM252 0V26C188 32 181 38 181 106V451C138 433 90 420 39 412V388C99 379 102 374 102 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562 495L592 498Z"/></g><g transform="matrix(.018,0,0,-0.018,10.747,0)"><use xlink:href="#g190-106"/></g><g transform="matrix(.018,0,0,-0.018,15.54,0)"><path id="g190-80" d="M381 665C170 665 44 498 44 318C44 125 188 -15 369 -15C552 -15 703 117 703 333C703 534 550 665 381 665ZM359 629C491 629 601 517 601 306C601 114 502 21 390 21C249 21 146 158 146 346S248 629 359 629Z"/></g><g transform="matrix(.013,0,0,-0.013,29.008,4.308)"><path id="g22-49" d="M310 382C345 404 366 417 384 433C404 450 417 474 417 501C417 578 357 635 252 635H251C184 635 135 603 107 572L57 506L86 478C122 527 156 554 205 554C250 554 290 528 290 467S227 367 144 340L151 300C168 304 190 308 208 308C260 308 327 275 327 181C327 89 288 49 238 49C177 49 131 93 109 111C95 122 82 119 70 110C57 100 40 82 40 63C40 48 48 34 65 21C86 4 126 -12 177 -12C240 -12 460 60 460 222C460 298 409 363 310 380V382Z"/></g></svg>-Based Piezoelectric Materials

<table>The effect of electric coupling factor in case of various dopants in BNKT.</table>

Advances in Materials Science and Engineering

fig1

Figure 1

Figure 1: Current Development in Lead-Free <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.524699pt" id="M1" height="16.2494pt" version="1.1" viewBox="-0.0657574 -11.7247 31.7305 16.2494" width="31.7305pt"><g transform="matrix(.018,0,0,-0.018,0,0)"><path id="g190-67" d="M372 352C427 368 507 407 507 502C507 548 486 592 451 616C420 638 376 650 301 650H44V622C124 616 128 610 128 527V123C128 40 122 34 36 28V0H257C336 0 402 12 453 40C512 72 548 124 548 191C548 291 471 335 372 350V352ZM213 362V558C213 591 216 602 226 608C235 614 258 618 282 618C377 618 415 558 415 490C415 406 369 362 260 362H213ZM213 328H258C380 328 450 283 450 181C450 76 377 35 296 34C231 34 213 53 213 125V328Z"/></g><g transform="matrix(.018,0,0,-0.018,10.373,0)"><path id="g190-106" d="M135 536C164 536 186 560 186 587C186 617 164 639 136 639C109 639 85 617 85 587C85 560 109 536 135 536ZM252 0V26C188 32 181 38 181 106V451C138 433 90 420 39 412V388C99 379 102 374 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385C156 397 171 404 190 404C241 404 275 364 275 291V274C253 256 180 229 120 209C65 190 39 159 39 110C39 47 88 -12 159 -12C189 -12 237 25 277 52C282 35 288 21 301 8C312 -3 333 -12 348 -12L433 39ZM275 84C256 65 221 48 195 48C164 48 124 73 124 124C124 161 146 180 185 198C206 208 254 229 275 240V84Z"/></g><g transform="matrix(.018,0,0,-0.018,26.859,0)"><path id="g190-45" d="M95 130C70 130 46 113 46 88C46 72 54 64 59 64C93 55 121 33 121 -3C121 -41 93 -68 44 -88L55 -117C117 -98 186 -56 186 22C186 91 131 130 95 130Z"/></g><g transform="matrix(.018,0,0,-0.018,30.937,0)"><path id="g190-76" d="M667 0V28C619 34 599 43 546 100C496 154 386 277 311 372C378 440 449 512 488 547C551 605 575 615 650 622V650H410V622L433 619C478 614 479 604 449 568C404 513 337 443 282 390C254 364 234 350 212 345V520C212 609 222 616 299 622V650H41V622C120 616 128 611 128 520V128C128 41 120 34 44 28V0H304V28C221 34 212 41 212 128V318C229 321 242 318 266 291C355 185 436 87 514 0H667Z"/></g><g 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562 495L592 498Z"/></g><g transform="matrix(.018,0,0,-0.018,10.747,0)"><use xlink:href="#g190-106"/></g><g transform="matrix(.018,0,0,-0.018,15.54,0)"><path id="g190-80" d="M381 665C170 665 44 498 44 318C44 125 188 -15 369 -15C552 -15 703 117 703 333C703 534 550 665 381 665ZM359 629C491 629 601 517 601 306C601 114 502 21 390 21C249 21 146 158 146 346S248 629 359 629Z"/></g><g transform="matrix(.013,0,0,-0.013,29.008,4.308)"><path id="g22-49" d="M310 382C345 404 366 417 384 433C404 450 417 474 417 501C417 578 357 635 252 635H251C184 635 135 603 107 572L57 506L86 478C122 527 156 554 205 554C250 554 290 528 290 467S227 367 144 340L151 300C168 304 190 308 208 308C260 308 327 275 327 181C327 89 288 49 238 49C177 49 131 93 109 111C95 122 82 119 70 110C57 100 40 82 40 63C40 48 48 34 65 21C86 4 126 -12 177 -12C240 -12 460 60 460 222C460 298 409 363 310 380V382Z"/></g></svg>-Based Piezoelectric Materials 

Advances in Materials Science and Engineering

Current Development in Lead-Free -Based Piezoelectric Materials

Figure 1