{"id":1706,"date":"2019-05-22T02:47:38","date_gmt":"2019-05-22T02:47:38","guid":{"rendered":"http:\/\/www.meetyoucarbide.com\/single-post-electrochemical-characterization-of-catalytic-materials\/"},"modified":"2020-05-04T13:12:07","modified_gmt":"2020-05-04T13:12:07","slug":"electrochemical-characterization-of-catalytic-materials","status":"publish","type":"post","link":"https:\/\/www.meetyoucarbide.com\/vi\/dac-tinh-dien-hoa-cua-vat-lieu-xuc-tac\/","title":{"rendered":"\u0110\u1eb7c t\u00ednh \u0111i\u1ec7n h\u00f3a c\u1ee7a v\u1eadt li\u1ec7u x\u00fac t\u00e1c"},"content":{"rendered":"
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C\u00f4ng ngh\u1ec7 ph\u1ea3n \u1ee9ng x\u00fac t\u00e1c \u0111i\u1ec7n l\u00e0 m\u1ed9t trong nh\u1eefng ph\u01b0\u01a1ng ph\u00e1p quan tr\u1ecdng th\u00fac \u0111\u1ea9y qu\u00e1 tr\u00ecnh chuy\u1ec3n \u0111\u1ed5i n\u0103ng l\u01b0\u1ee3ng v\u00e0 l\u00e0m s\u1ea1ch m\u00f4i tr\u01b0\u1eddng.<\/div>\n
Trong nh\u1eefng n\u0103m g\u1ea7n \u0111\u00e2y, v\u1edbi s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a x\u00e3 h\u1ed9i v\u00e0 s\u1ef1 ti\u1ebfn b\u1ed9 c\u1ee7a nh\u00e2n lo\u1ea1i, c\u00e1c v\u1ea5n \u0111\u1ec1 v\u1ec1 n\u0103ng l\u01b0\u1ee3ng v\u00e0 m\u00f4i tr\u01b0\u1eddng ng\u00e0y c\u00e0ng nghi\u00eam tr\u1ecdng \u0111\u00e3 tr\u1edf th\u00e0nh m\u1ed9t v\u1ea5n \u0111\u1ec1 to\u00e0n th\u1ebf gi\u1edbi c\u1ea7n \u0111\u01b0\u1ee3c gi\u1ea3i quy\u1ebft c\u1ea5p b\u00e1ch. M\u1ecdi ng\u01b0\u1eddi cam k\u1ebft s\u1eed d\u1ee5ng hi\u1ec7u qu\u1ea3 c\u00e1c ngu\u1ed3n n\u0103ng l\u01b0\u1ee3ng m\u1edbi v\u00e0 c\u00e1c ph\u01b0\u01a1ng ph\u00e1p thanh l\u1ecdc m\u00f4i tr\u01b0\u1eddng l\u00e2u d\u00e0i. C\u00e1c ph\u01b0\u01a1ng ph\u00e1p nghi\u00ean c\u1ee9u hi\u1ec7u qu\u1ea3 hi\u1ec7n nay \u0111\u1ec3 th\u00fac \u0111\u1ea9y chuy\u1ec3n \u0111\u1ed5i n\u0103ng l\u01b0\u1ee3ng v\u00e0 l\u00e0m s\u1ea1ch m\u00f4i tr\u01b0\u1eddng li\u00ean quan \u0111\u1ebfn nhi\u1ec1u h\u01b0\u1edbng, ch\u1eb3ng h\u1ea1n nh\u01b0 ph\u00e1t tri\u1ec3n pin nhi\u00ean li\u1ec7u, s\u1ea3n xu\u1ea5t hydro, t\u00e0i nguy\u00ean CO2, chuy\u1ec3n \u0111\u1ed5i x\u00fac t\u00e1c h\u1eefu c\u01a1 c\u1ee7a kh\u00ed th\u1ea3i. C\u00e1c ph\u01b0\u01a1ng ph\u00e1p th\u1eed nghi\u1ec7m \u0111i\u1ec7n h\u00f3a nh\u01b0 m\u1ed9t h\u01b0\u1edbng d\u1eabn l\u00fd thuy\u1ebft cung c\u1ea5p m\u1ed9t ph\u01b0\u01a1ng ti\u1ec7n gi\u1ea3i th\u00edch h\u1ee3p l\u00fd cho s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a hi\u1ec7u su\u1ea5t \u0111i\u1ec7n x\u00fac t\u00e1c. B\u00e0i b\u00e1o n\u00e0y t\u00f3m t\u1eaft c\u00e1c ph\u01b0\u01a1ng ph\u00e1p th\u1eed \u0111i\u1ec7n h\u00f3a th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong m\u1ed9t s\u1ed1 ph\u1ea3n \u1ee9ng \u0111i\u1ec7n h\u00f3a.<\/div>\n
H\u00ecnh 1 Qu\u00e1 tr\u00ecnh \u0111i\u1ec7n x\u00fac t\u00e1c chuy\u1ec3n \u0111\u1ed5i n\u0103ng l\u01b0\u1ee3ng b\u1ec1n v\u1eefng<\/div>\n

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1. \u0111o \u0111i\u1ec7n \u00e1p v\u00f2ng<\/h2>\n
\u0110o V\u00f4n theo chu k\u1ef3 (CV) l\u00e0 ph\u01b0\u01a1ng ph\u00e1p nghi\u00ean c\u1ee9u \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng ph\u1ed5 bi\u1ebfn nh\u1ea5t \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 c\u00e1c h\u1ec7 th\u1ed1ng \u0111i\u1ec7n h\u00f3a ch\u01b0a bi\u1ebft. N\u00f3 ch\u1ee7 y\u1ebfu thu \u0111\u01b0\u1ee3c b\u1eb1ng c\u00e1ch ki\u1ec3m so\u00e1t th\u1ebf \u0111i\u1ec7n c\u1ef1c \u1edf c\u00e1c t\u1ed1c \u0111\u1ed9 kh\u00e1c nhau v\u00e0 qu\u00e9t m\u1ed9t ho\u1eb7c nhi\u1ec1u l\u1ea7n v\u1edbi d\u1ea1ng s\u00f3ng tam gi\u00e1c theo th\u1eddi gian. \u0110\u01b0\u1eddng cong hi\u1ec7n t\u1ea1i-ti\u1ec1m n\u0103ng (iE). C\u00e1c ph\u1ea3n \u1ee9ng kh\u1eed v\u00e0 ph\u1ea3n \u1ee9ng oxi h\u00f3a kh\u00e1c nhau c\u00f3 th\u1ec3 x\u1ea3y ra lu\u00e2n phi\u00ean tr\u00ean c\u00e1c \u0111i\u1ec7n c\u1ef1c trong c\u00e1c d\u00e3y th\u1ebf kh\u00e1c nhau. T\u00ednh thu\u1eadn ngh\u1ecbch c\u1ee7a ph\u1ea3n \u1ee9ng \u0111i\u1ec7n c\u1ef1c c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c \u0111\u00e1nh gi\u00e1 theo h\u00ecnh d\u1ea1ng c\u1ee7a \u0111\u01b0\u1eddng cong; c\u00e1c \u0111\u1ec9nh h\u1ea5p ph\u1ee5 v\u00e0 gi\u1ea3i h\u1ea5p ph\u1ee5 c\u1ee7a ch\u1ea5t ph\u1ea3n \u1ee9ng c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 ch\u1ea5t x\u00fac t\u00e1c \u0111i\u1ec7n theo ph\u1ea1m vi th\u1ebf c\u1ee5 th\u1ec3. Khu v\u1ef1c ho\u1ea1t \u0111\u1ed9ng c\u1ee7a x\u00fac t\u00e1c c\u0169ng c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 thu \u0111\u01b0\u1ee3c th\u00f4ng tin h\u1eefu \u00edch v\u1ec1 c\u00e1c ph\u1ea3n \u1ee9ng \u0111i\u1ec7n c\u1ef1c ph\u1ee9c t\u1ea1p.<\/div>\n
H\u00ecnh 1.1 Qu\u00e9t \u0111\u01b0\u1eddng cong \u0111\u00e1p \u1ee9ng ti\u1ec1m n\u0103ng hi\u1ec7n t\u1ea1i<\/div>\n

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Nh\u01b0 trong h\u00ecnh 1.1, \u0111i\u1ec7n th\u1ebf c\u1ee7a n\u1eeda \u0111\u1ea7u \u0111\u01b0\u1ee3c qu\u00e9t v\u1ec1 ph\u00eda cat\u1ed1t, v\u00e0 ch\u1ea5t ho\u1ea1t t\u00ednh b\u1ecb kh\u1eed tr\u00ean \u0111i\u1ec7n c\u1ef1c \u0111\u1ec3 t\u1ea1o ra s\u00f3ng kh\u1eed. Khi \u0111i\u1ec7n th\u1ebf c\u1ee7a n\u1eeda sau \u0111\u01b0\u1ee3c qu\u00e9t v\u1ec1 ph\u00eda c\u1ef1c d\u01b0\u01a1ng, s\u1ea3n ph\u1ea9m kh\u1eed l\u1ea1i b\u1ecb oxi h\u00f3a tr\u00ean \u0111i\u1ec7n c\u1ef1c \u0111\u1ec3 t\u1ea1o ra s\u00f3ng oxi h\u00f3a. Hai tham s\u1ed1 h\u1eefu \u00edch c\u1ee7a \u0111\u01b0\u1eddng cong iE \u0111o v\u00f4n theo chu k\u1ef3 l\u00e0 t\u1ef7 s\u1ed1 d\u00f2ng \u0111i\u1ec7n \u0111\u1ec9nh ipa \/ ipc v\u00e0 hi\u1ec7u \u0111i\u1ec7n th\u1ebf \u0111\u1ec9nh Epa-Epc. \u0110\u1ed1i v\u1edbi s\u00f3ng Nernst c\u1ee7a s\u1ea3n ph\u1ea9m \u1ed5n \u0111\u1ecbnh, t\u1ef7 l\u1ec7 d\u00f2ng \u0111i\u1ec7n \u0111\u1ec9nh ipa \/ ipc = 1, kh\u00f4ng ph\u1ee5 thu\u1ed9c v\u00e0o t\u1ed1c \u0111\u1ed9 qu\u00e9t, h\u1ec7 s\u1ed1 khu\u1ebfch t\u00e1n v\u00e0 \u0111i\u1ec7n th\u1ebf giao ho\u00e1n. Khi qu\u00e1 tr\u00ecnh qu\u00e9t cat\u1ed1t b\u1ecb d\u1eebng l\u1ea1i, d\u00f2ng \u0111i\u1ec7n b\u1ecb suy gi\u1ea3m v\u1ec1 0 v\u00e0 sau \u0111\u00f3 ng\u01b0\u1ee3c l\u1ea1i scand. \u0110\u01b0\u1eddng cong iE thu \u0111\u01b0\u1ee3c ho\u00e0n to\u00e0n gi\u1ed1ng v\u1edbi \u0111\u01b0\u1eddng cong cat\u1ed1t, nh\u01b0ng \u0111\u01b0\u1ee3c v\u1ebd theo h\u01b0\u1edbng ng\u01b0\u1ee3c l\u1ea1i c\u1ee7a t\u1ecda \u0111\u1ed9 I v\u00e0 t\u1ecda \u0111\u1ed9 E. T\u1ef7 l\u1ec7 ipa \/ ipc l\u1ec7ch 1, cho th\u1ea5y r\u1eb1ng qu\u00e1 tr\u00ecnh \u0111i\u1ec7n c\u1ef1c kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t qu\u00e1 tr\u00ecnh ph\u1ea3n \u1ee9ng thu\u1eadn ngh\u1ecbch ho\u00e0n to\u00e0n li\u00ean quan \u0111\u1ebfn \u0111\u1ed9ng h\u1ecdc \u0111\u1ed3ng nh\u1ea5t ho\u1eb7c c\u00e1c bi\u1ebfn ch\u1ee9ng kh\u00e1c. Chi\u1ec1u cao pic ph\u1ea3n \u1ee9ng v\u00e0 di\u1ec7n t\u00edch pic c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u01b0\u1edbc t\u00ednh c\u00e1c th\u00f4ng s\u1ed1 c\u1ee7a h\u1ec7 th\u1ed1ng nh\u01b0 n\u1ed3ng \u0111\u1ed9 c\u1ee7a c\u00e1c ch\u1ea5t \u0111i\u1ec7n h\u00f3a ho\u1eb7c h\u1eb1ng s\u1ed1 v\u1eadn t\u1ed1c c\u1ee7a ph\u1ea3n \u1ee9ng \u0111\u1ed3ng th\u1ec3 li\u00ean k\u1ebft. Tuy nhi\u00ean, \u0111\u01b0\u1eddng cong CV kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p \u0111\u1ecbnh l\u01b0\u1ee3ng l\u00fd t\u01b0\u1edfng, v\u00e0 c\u00f4ng d\u1ee5ng m\u1ea1nh m\u1ebd c\u1ee7a n\u00f3 l\u00e0 \u1edf kh\u1ea3 n\u0103ng \u0110\u00e1nh gi\u00e1 b\u00e1n \u0111\u1ecbnh l\u01b0\u1ee3ng.<\/div>\n

2. \u0111o voltulse<\/h2>\n
\u0110o \u0111i\u1ec7n \u00e1p xung l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p \u0111o \u0111i\u1ec7n h\u00f3a d\u1ef1a tr\u00ean ho\u1ea1t \u0111\u1ed9ng c\u1ee7a c\u00e1c \u0111i\u1ec7n c\u1ef1c ph\u00e2n c\u1ef1c. N\u00f3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 nghi\u00ean c\u1ee9u qu\u00e1 tr\u00ecnh oxy h\u00f3a kh\u1eed trong c\u00e1c m\u00f4i tr\u01b0\u1eddng kh\u00e1c nhau, s\u1ef1 h\u1ea5p ph\u1ee5 c\u1ee7a v\u1eadt li\u1ec7u b\u1ec1 m\u1eb7t tr\u00ean v\u1eadt li\u1ec7u x\u00fac t\u00e1c v\u00e0 c\u01a1 ch\u1ebf truy\u1ec1n \u0111i\u1ec7n t\u1eed tr\u00ean b\u1ec1 m\u1eb7t c\u1ee7a c\u00e1c \u0111i\u1ec7n c\u1ef1c bi\u1ebfn \u0111\u1ed5i v\u1ec1 m\u1eb7t h\u00f3a h\u1ecdc. Ph\u00e1t hi\u1ec7n \u0111\u1eb7c bi\u1ec7t hi\u1ec7u qu\u1ea3. Ph\u00e9p \u0111o \u0111i\u1ec7n \u00e1p xung bao g\u1ed3m ph\u00e9p \u0111o \u0111i\u1ec7n \u00e1p b\u01b0\u1edbc, ph\u00e9p \u0111o \u0111i\u1ec7n \u00e1p xung th\u00f4ng th\u01b0\u1eddng, ph\u00e9p \u0111o \u0111i\u1ec7n th\u1ebf xung vi sai v\u00e0 ph\u00e9p \u0111o \u0111i\u1ec7n th\u1ebf s\u00f3ng vu\u00f4ng t\u00f9y thu\u1ed9c v\u00e0o c\u00e1ch qu\u00e9t \u0111i\u1ec7n \u00e1p. Trong s\u1ed1 \u0111\u00f3, ph\u00e9p \u0111o v\u00f4n b\u01b0\u1edbc t\u01b0\u01a1ng t\u1ef1 nh\u01b0 ph\u01b0\u01a1ng ph\u00e1p qu\u00e9t ti\u1ec1m n\u0103ng v\u00e0 ph\u1ea3n \u1ee9ng c\u1ee7a h\u1ea7u h\u1ebft c\u00e1c h\u1ec7 th\u1ed1ng \u0111\u1ed1i v\u1edbi v\u00f4n-ampe b\u01b0\u1edbc c\u00f3 \u0111\u1ed9 ph\u00e2n gi\u1ea3i cao h\u01a1n (\u0394E <5 mV) r\u1ea5t gi\u1ed1ng v\u1edbi k\u1ebft qu\u1ea3 th\u00ed nghi\u1ec7m qu\u00e9t tuy\u1ebfn t\u00ednh c\u00f3 c\u00f9ng t\u1ed1c \u0111\u1ed9 qu\u00e9t.<\/div>\n

3. quang ph\u1ed5 tr\u1edf kh\u00e1ng \u0111i\u1ec7n h\u00f3a<\/h2>\n
Quang ph\u1ed5 tr\u1edf kh\u00e1ng \u0111i\u1ec7n h\u00f3a l\u00e0 \u00e1p d\u1ee5ng m\u1ed9t t\u00edn hi\u1ec7u \u0111i\u1ec7n nhi\u1ec5u lo\u1ea1n v\u00e0o h\u1ec7 th\u1ed1ng \u0111i\u1ec7n h\u00f3a. Kh\u00f4ng gi\u1ed1ng nh\u01b0 ph\u01b0\u01a1ng ph\u00e1p qu\u00e9t tuy\u1ebfn t\u00ednh, h\u1ec7 th\u1ed1ng \u0111i\u1ec7n h\u00f3a \u1edf xa tr\u1ea1ng th\u00e1i c\u00e2n b\u1eb1ng, sau \u0111\u00f3 ph\u1ea3n \u1ee9ng c\u1ee7a h\u1ec7 th\u1ed1ng \u0111\u01b0\u1ee3c quan s\u00e1t, v\u00e0 c\u00e1c t\u00ednh ch\u1ea5t \u0111i\u1ec7n h\u00f3a c\u1ee7a h\u1ec7 th\u1ed1ng \u0111\u01b0\u1ee3c ph\u00e2n t\u00edch b\u1eb1ng t\u00edn hi\u1ec7u \u0111i\u1ec7n \u0111\u00e1p \u1ee9ng. Ph\u1ed5 tr\u1edf kh\u00e1ng \u0111i\u1ec7n h\u00f3a th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 ph\u00e2n t\u00edch, \u0111\u00e1nh gi\u00e1 ph\u1ea3n \u1ee9ng ORR trong pin nhi\u00ean li\u1ec7u PEM, m\u00f4 t\u1ea3 \u0111\u1eb7c \u0111i\u1ec3m t\u1ed5n th\u1ea5t khu\u1ebfch t\u00e1n tr\u00ean b\u1ec1 m\u1eb7t v\u1eadt li\u1ec7u x\u00fac t\u00e1c, \u01b0\u1edbc t\u00ednh \u0111i\u1ec7n tr\u1edf ohmic, \u0111\u1eb7c \u0111i\u1ec3m c\u1ee7a tr\u1edf kh\u00e1ng truy\u1ec1n \u0111i\u1ec7n t\u00edch v\u00e0 \u0111i\u1ec7n dung l\u1edbp k\u00e9p \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 v\u00e0 t\u1ed1i \u01b0u h\u00f3a c\u1ee5m \u0111i\u1ec7n c\u1ef1c m\u00e0ng.<\/div>\n
Ph\u1ed5 tr\u1edf kh\u00e1ng th\u01b0\u1eddng \u0111\u01b0\u1ee3c v\u1ebd d\u01b0\u1edbi d\u1ea1ng bi\u1ec3u \u0111\u1ed3 Bode v\u00e0 bi\u1ec3u \u0111\u1ed3 Nyquist. Trong bi\u1ec3u \u0111\u1ed3 Bode, \u0111\u1ed9 l\u1edbn v\u00e0 pha c\u1ee7a tr\u1edf kh\u00e1ng \u0111\u01b0\u1ee3c v\u1ebd d\u01b0\u1edbi d\u1ea1ng m\u1ed9t h\u00e0m c\u1ee7a t\u1ea7n s\u1ed1; trong bi\u1ec3u \u0111\u1ed3 Nyquist, ph\u1ea7n \u1ea3o c\u1ee7a tr\u1edf kh\u00e1ng \u0111\u01b0\u1ee3c v\u1ebd \u1edf m\u1ed7i \u0111i\u1ec3m t\u1ea7n s\u1ed1 so v\u1edbi ph\u1ea7n th\u1ef1c. H\u1ed3 quang t\u1ea7n s\u1ed1 cao ph\u1ea3n \u00e1nh s\u1ef1 k\u1ebft h\u1ee3p c\u1ee7a \u0111i\u1ec7n dung l\u1edbp k\u00e9p c\u1ee7a l\u1edbp x\u00fac t\u00e1c, tr\u1edf kh\u00e1ng truy\u1ec1n \u0111i\u1ec7n t\u00edch hi\u1ec7u d\u1ee5ng v\u00e0 \u0111i\u1ec7n tr\u1edf ohmic, ph\u1ea3n \u00e1nh tr\u1edf kh\u00e1ng \u0111\u01b0\u1ee3c t\u1ea1o ra b\u1edfi qu\u00e1 tr\u00ecnh truy\u1ec1n kh\u1ed1i. \u0110\u1ed1i v\u1edbi m\u1ed9t h\u1ec7 th\u1ed1ng nh\u1ea5t \u0111\u1ecbnh, hai v\u00f9ng \u0111\u00f4i khi kh\u00f4ng \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh r\u00f5 r\u00e0ng.<\/div>\n
H\u00ecnh 3.1 Ph\u1ed5 tr\u1edf kh\u00e1ng c\u1ee7a h\u1ec7 th\u1ed1ng \u0111i\u1ec7n h\u00f3a<\/div>\n

\"\"<\/p>\n

H\u00ecnh 3.1 cho th\u1ea5y c\u00e1c \u0111\u1eb7c t\u00ednh c\u1ef1c h\u1ea1n c\u1ee7a \u0111i\u1ec1u khi\u1ec3n \u0111\u1ed9ng h\u1ecdc v\u00e0 \u0111i\u1ec1u khi\u1ec3n truy\u1ec1n kh\u1ed1i. Tuy nhi\u00ean, \u0111\u1ed1i v\u1edbi b\u1ea5t k\u1ef3 h\u1ec7 th\u1ed1ng nh\u1ea5t \u0111\u1ecbnh n\u00e0o, hai v\u00f9ng c\u00f3 th\u1ec3 kh\u00f4ng \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh r\u00f5 r\u00e0ng. Y\u1ebfu t\u1ed1 quy\u1ebft \u0111\u1ecbnh l\u00e0 m\u1ed1i quan h\u1ec7 gi\u1eefa \u0111i\u1ec7n tr\u1edf truy\u1ec1n \u0111i\u1ec7n t\u00edch v\u00e0 tr\u1edf kh\u00e1ng truy\u1ec1n t\u1ea3i. N\u1ebfu h\u1ec7 th\u1ed1ng h\u00f3a h\u1ecdc ch\u1eadm \u0111\u1ed9ng h\u1ecdc, n\u00f3 s\u1ebd hi\u1ec3n th\u1ecb Rct l\u1edbn, d\u01b0\u1eddng nh\u01b0 c\u00f3 m\u1ed9t v\u00f9ng t\u1ea7n s\u1ed1 r\u1ea5t h\u1ea1n ch\u1ebf. Khi h\u1ec7 th\u1ed1ng \u0111\u1ed9ng, Chuy\u1ec3n giao v\u1eadt ch\u1ea5t lu\u00f4n \u0111\u00f3ng vai tr\u00f2 ch\u1ee7 \u0111\u1ea1o, v\u00e0 c\u00e1c v\u00f9ng b\u00e1n nguy\u1ec7t r\u1ea5t kh\u00f3 x\u00e1c \u0111\u1ecbnh.<\/div>\n

4. Chronoamperometry<\/h2>\n
Ph\u01b0\u01a1ng ph\u00e1p \u0111o th\u1eddi gian l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p \u0111i\u1ec1u khi\u1ec3n qu\u00e1 \u0111\u1ed9 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 s\u1ef1 h\u1ea5p ph\u1ee5 v\u00e0 khu\u1ebfch t\u00e1n c\u1ee7a b\u1ec1 m\u1eb7t ch\u1ea5t x\u00fac t\u00e1c. \u0110\u01b0\u1eddng cong \u0111o th\u1eddi gian thu \u0111\u01b0\u1ee3c b\u1eb1ng c\u00e1ch \u00e1p d\u1ee5ng m\u1ed9t b\u01b0\u1edbc \u0111i\u1ec7n th\u1ebf v\u00e0o h\u1ec7 th\u1ed1ng \u0111i\u1ec7n h\u00f3a \u0111\u1ec3 \u0111o s\u1ef1 thay \u0111\u1ed5i c\u1ee7a t\u00edn hi\u1ec7u \u0111\u00e1p \u1ee9ng d\u00f2ng \u0111i\u1ec7n theo th\u1eddi gian. Khi cho m\u1ed9t b\u01b0\u1edbc \u0111i\u1ec7n th\u1ebf, d\u1ea1ng s\u00f3ng c\u01a1 b\u1ea3n \u0111\u01b0\u1ee3c th\u1ec3 hi\u1ec7n trong H\u00ecnh 4.1 (a), v\u00e0 b\u1ec1 m\u1eb7t c\u1ee7a \u0111i\u1ec7n c\u1ef1c r\u1eafn \u0111\u01b0\u1ee3c ph\u00e2n t\u00edch v\u1edbi m\u1ed9t ch\u1ea5t ho\u1ea1t t\u00ednh. Sau khi b\u01b0\u1edbc \u0111i\u1ec7n th\u1ebf \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng, c\u00e1c lo\u1ea1i \u0111i\u1ec7n c\u1ef1c g\u1ea7n b\u1ec1 m\u1eb7t c\u1ee7a \u0111i\u1ec7n c\u1ef1c \u0111\u1ea7u ti\u00ean b\u1ecb kh\u1eed th\u00e0nh g\u1ed1c anion \u1ed5n \u0111\u1ecbnh, \u0111\u00f2i h\u1ecfi m\u1ed9t d\u00f2ng \u0111i\u1ec7n l\u1edbn v\u00ec qu\u00e1 tr\u00ecnh x\u1ea3y ra ngay l\u1eadp t\u1ee9c \u1edf b\u01b0\u1edbc t\u1ee9c th\u1eddi. D\u00f2ng \u0111i\u1ec7n ch\u1ea1y sau \u0111\u00f3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 duy tr\u00ec c\u00e1c \u0111i\u1ec1u ki\u1ec7n m\u00e0 ch\u1ea5t ho\u1ea1t \u0111\u1ed9ng b\u1ec1 m\u1eb7t \u0111i\u1ec7n c\u1ef1c b\u1ecb gi\u1ea3m ho\u00e0n to\u00e0n. S\u1ef1 gi\u1ea3m ban \u0111\u1ea7u g\u00e2y ra m\u1ed9t gradient n\u1ed3ng \u0111\u1ed9 (t\u1ee9c l\u00e0 n\u1ed3ng \u0111\u1ed9) gi\u1eefa b\u1ec1 m\u1eb7t \u0111i\u1ec7n c\u1ef1c v\u00e0 dung d\u1ecbch kh\u1ed1i, v\u00e0 do \u0111\u00f3 ch\u1ea5t ho\u1ea1t \u0111\u1ed9ng b\u1eaft \u0111\u1ea7u li\u00ean t\u1ee5c khu\u1ebfch t\u00e1n v\u1ec1 ph\u00eda b\u1ec1 m\u1eb7t v\u00e0 khu\u1ebfch t\u00e1n \u0111\u1ebfn \u0111i\u1ec7n c\u1ef1c. C\u00e1c ch\u1ea5t ho\u1ea1t \u0111\u1ed9ng tr\u00ean b\u1ec1 m\u1eb7t ho\u00e0n to\u00e0n gi\u1ea3m ngay l\u1eadp t\u1ee9c. D\u00f2ng khu\u1ebfch t\u00e1n, ngh\u0129a l\u00e0, d\u00f2ng \u0111i\u1ec7n, t\u1ef7 l\u1ec7 v\u1edbi gradien n\u1ed3ng \u0111\u1ed9 c\u1ee7a b\u1ec1 m\u1eb7t \u0111i\u1ec7n c\u1ef1c. Tuy nhi\u00ean, l\u01b0u \u00fd r\u1eb1ng khi ph\u1ea3n \u1ee9ng ti\u1ebfp t\u1ee5c, ch\u1ea5t ho\u1ea1t \u0111\u1ed9ng trong dung d\u1ecbch kh\u1ed1i khu\u1ebfch t\u00e1n li\u00ean t\u1ee5c v\u1ec1 ph\u00eda b\u1ec1 m\u1eb7t c\u1ee7a \u0111i\u1ec7n c\u1ef1c, l\u00e0m cho v\u00f9ng gradient n\u1ed3ng \u0111\u1ed9 m\u1edf r\u1ed9ng d\u1ea7n v\u1ec1 ph\u00eda dung d\u1ecbch kh\u1ed1i, v\u00e0 gradient n\u1ed3ng \u0111\u1ed9 b\u1ec1 m\u1eb7t c\u1ee7a \u0111i\u1ec7n c\u1ef1c r\u1eafn d\u1ea7n d\u1ea7n tr\u1edf n\u00ean nh\u1ecf h\u01a1n (c\u1ea1n ki\u1ec7t), v\u00e0 d\u00f2ng \u0111i\u1ec7n d\u1ea7n d\u1ea7n thay \u0111\u1ed5i. nh\u1ecf b\u00e9. S\u1ef1 ph\u00e2n b\u1ed1 n\u1ed3ng \u0111\u1ed9 v\u00e0 d\u00f2ng \u0111i\u1ec7n so v\u1edbi th\u1eddi gian \u0111\u01b0\u1ee3c th\u1ec3 hi\u1ec7n trong H\u00ecnh 4.1 (b) v\u00e0 H\u00ecnh 4.1 (c).<\/div>\n
H\u00ecnh 4.1 (a) D\u1ea1ng s\u00f3ng th\u1ef1c nghi\u1ec7m b\u01b0\u1edbc, ch\u1ea5t ph\u1ea3n \u1ee9ng O kh\u00f4ng ph\u1ea3n \u1ee9ng \u1edf th\u1ebf E1, b\u1ecb gi\u1ea3m \u1edf E2 \u1edf t\u1ed1c \u0111\u1ed9 gi\u1edbi h\u1ea1n khu\u1ebfch t\u00e1n; (b) s\u1ef1 ph\u00e2n b\u1ed1 n\u1ed3ng \u0111\u1ed9 t\u1ea1i c\u00e1c th\u1eddi \u0111i\u1ec3m kh\u00e1c nhau; (c) hi\u1ec7n t\u1ea1i so v\u1edbi \u0111\u01b0\u1eddng cong th\u1eddi gian<\/div>\n

\"\"<\/p>\n

5. c\u00f4ng ngh\u1ec7 \u0111i\u1ec7n c\u1ef1c \u0111\u0129a chuy\u1ec3n \u0111\u1ed9ng<\/h2>\n
C\u00f4ng ngh\u1ec7 \u0111i\u1ec7n c\u1ef1c \u0111\u0129a quay (RDE) r\u1ea5t h\u1eefu \u00edch trong vi\u1ec7c nghi\u00ean c\u1ee9u ph\u1ea3n \u1ee9ng \u0111\u1ed3ng nh\u1ea5t li\u00ean k\u1ebft c\u1ee7a b\u1ec1 m\u1eb7t ch\u1ea5t x\u00fac t\u00e1c, do \u0111\u00f3 ph\u1ea3n \u1ee9ng \u0111i\u1ec7n h\u00f3a tr\u00ean b\u1ec1 m\u1eb7t ch\u1ea5t x\u00fac t\u00e1c \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n trong \u0111i\u1ec1u ki\u1ec7n tr\u1ea1ng th\u00e1i t\u01b0\u01a1ng \u0111\u1ed1i \u1ed5n \u0111\u1ecbnh. RDE c\u00f3 th\u1ec3 ki\u1ec3m so\u00e1t c\u00e1c ch\u1ea5t c\u00f3 \u0111\u1ed9 khu\u1ebfch t\u00e1n ch\u1eadm h\u01a1n, ch\u1eb3ng h\u1ea1n nh\u01b0 kh\u00ed d\u1ec5 d\u00e0ng khu\u1ebfch t\u00e1n v\u00e0o dung d\u1ecbch, gi\u1ea3m \u1ea3nh h\u01b0\u1edfng c\u1ee7a l\u1edbp khu\u1ebfch t\u00e1n \u0111\u1ebfn s\u1ef1 ph\u00e2n b\u1ed1 m\u1eadt \u0111\u1ed9 d\u00f2ng \u0111i\u1ec7n. Do \u0111\u00f3, m\u1eadt \u0111\u1ed9 d\u00f2ng \u0111i\u1ec7n \u1ed5n \u0111\u1ecbnh thu \u0111\u01b0\u1ee3c, \u1edf tr\u1ea1ng th\u00e1i \u1ed5n \u0111\u1ecbnh g\u1ea7n \u0111\u00fang, c\u00f3 l\u1ee3i cho qu\u00e1 tr\u00ecnh ph\u00e2n t\u00edch \u0111i\u1ec7n h\u00f3a; RDE c\u00f3 th\u1ec3 \u0111i\u1ec1u khi\u1ec3n t\u1ed1c \u0111\u1ed9 ch\u1ea5t \u0111i\u1ec7n ph\u00e2n \u0111\u1ebfn b\u1ec1 m\u1eb7t \u0111i\u1ec7n c\u1ef1c b\u1eb1ng c\u00e1ch \u0111i\u1ec1u ch\u1ec9nh t\u1ed1c \u0111\u1ed9 quay v\u00e0 \u0111o c\u00e1c th\u00f4ng s\u1ed1 c\u1ee7a qu\u00e1 tr\u00ecnh ph\u1ea3n \u1ee9ng \u0111i\u1ec7n c\u1ef1c \u1edf c\u00e1c t\u1ed1c \u0111\u1ed9 quay kh\u00e1c nhau. ph\u00e2n t\u00edch.<\/div>\n
Khi con ng\u01b0\u1eddi tr\u1edf n\u00ean quan t\u00e2m h\u01a1n \u0111\u1ebfn vi\u1ec7c ph\u00e1t tri\u1ec3n c\u00e1c ch\u1ea5t x\u00fac t\u00e1c \u0111i\u1ec7n ti\u00ean ti\u1ebfn \u0111\u1ec3 chuy\u1ec3n \u0111\u1ed5i n\u0103ng l\u01b0\u1ee3ng s\u1ea1ch, ngo\u00e0i vi\u1ec7c nh\u1ea5n m\u1ea1nh vi\u1ec7c s\u1eed d\u1ee5ng m\u1ed9t s\u1ed1 ph\u01b0\u01a1ng ph\u00e1p c\u01a1 b\u1ea3n \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh \u0111\u1eb7c \u0111i\u1ec3m c\u1ee7a c\u00e1c ph\u1ea3n \u1ee9ng \u0111i\u1ec7n x\u00fac t\u00e1c, c\u1ea7n ki\u1ec3m tra th\u00eam c\u00e1c b\u01b0\u1edbc c\u01a1 b\u1ea3n c\u1ee7a m\u1ed7i ph\u1ea3n \u1ee9ng \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh s\u1ef1 k\u1ebft h\u1ee3p c\u1ee7a ch\u00eca kh\u00f3a ch\u1ea5t trung gian, b\u1ec1 m\u1eb7t c\u1ee7a ch\u1ea5t trung gian, v\u00e0 n\u0103ng l\u01b0\u1ee3ng c\u1ee7a m\u1ed7i b\u01b0\u1edbc ph\u1ea3n \u1ee9ng c\u01a1 b\u1ea3n. Vi\u1ec7c nghi\u00ean c\u1ee9u c\u00e1c ph\u01b0\u01a1ng ph\u00e1p \u0111i\u1ec7n h\u00f3a v\u1eabn c\u00f2n \u0111\u00f2i h\u1ecfi nhi\u1ec1u chi ti\u1ebft v\u1ec1 giao di\u1ec7n \u0111i\u1ec7n c\u1ef1c - ch\u1ea5t \u0111i\u1ec7n ph\u00e2n m\u00e0 cho \u0111\u1ebfn nay v\u1eabn ch\u01b0a \u0111\u01b0\u1ee3c bi\u1ebft \u0111\u1ebfn, ch\u1eb3ng h\u1ea1n nh\u01b0 c\u00e1c r\u00e0o c\u1ea3n \u0111\u1ed9ng h\u1ecdc v\u00e0 ph\u1ea3n \u1ee9ng li\u00ean quan \u0111\u1ebfn c\u00e1c b\u01b0\u1edbc c\u01a1 b\u1ea3n ch\u00ednh c\u1ee7a s\u1ef1 chuy\u1ec3n proton \/ electron; g\u1ea7n dung m\u00f4i, cation v\u00e0 giao di\u1ec7n ph\u1ea3n \u1ee9ng. M\u00f4 t\u1ea3 tr\u1ea1ng th\u00e1i nguy\u00ean t\u1eed, c\u1ea5p \u0111\u1ed9 ph\u00e2n t\u1eed c\u1ee7a anion; v\u00e0 c\u00e1c ph\u01b0\u01a1ng ph\u00e1p thu t\u00edn hi\u1ec7u th\u1eddi gian th\u1ef1c nhanh h\u01a1n v\u00e0 hi\u1ec7u qu\u1ea3 h\u01a1n trong su\u1ed1t qu\u00e1 tr\u00ecnh ph\u1ea3n \u1ee9ng \u0111i\u1ec7n h\u00f3a v\u1eabn \u0111i \u0111\u1ea7u trong c\u00e1c ph\u1ea3n \u1ee9ng \u0111i\u1ec7n x\u00fac t\u00e1c. T\u00f3m l\u1ea1i, vi\u1ec7c nghi\u00ean c\u1ee9u s\u00e2u c\u00e1c ph\u01b0\u01a1ng ph\u00e1p x\u00e1c \u0111\u1ecbnh \u0111\u1eb7c t\u00ednh \u0111i\u1ec7n h\u00f3a cung c\u1ea5p m\u1ed9t chi\u1ebfn l\u01b0\u1ee3c \u0111\u1ecbnh h\u01b0\u1edbng cho vi\u1ec7c ph\u00e1t tri\u1ec3n c\u00e1c h\u1ec7 th\u1ed1ng x\u00fac t\u00e1c m\u1edbi hi\u1ec7u su\u1ea5t cao.<\/div>\n<\/div>\n<\/div>\n

<\/p>","protected":false},"excerpt":{"rendered":"

Electrocatalytic reaction technology is one of the key methods driving these energy conversion and environmental purification pathways. In recent years, with the development of society and the progress of mankind, increasingly serious energy and environmental problems have become a worldwide problem that needs to be solved urgently. People are committed to the effective use of…<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[79],"tags":[],"class_list":["post-1706","post","type-post","status-publish","format-standard","hentry","category-materials-weekly"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/posts\/1706","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/comments?post=1706"}],"version-history":[{"count":0,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/posts\/1706\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/media?parent=1706"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/categories?post=1706"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/vi\/wp-json\/wp\/v2\/tags?post=1706"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}